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Birmingham, MI, 48009


Metro Detroit and Michigan wedding photographer 


Filtering by Tag: photography

Cheetah Softboxes Compared

Robert Hall

In my newest video I compared the 6 different softbox options available from Cheetah. 

This includes the Quick SoupBowl (QSB-26, QSB-34, QSB-42), Quick RiceBowl (QRB-36, QRB-48) and Max20.

26" QSB-26
34” QSB-34
42” QSB-42
36” QRB-36
48” QRB-48 (quick out of stock, here's the rod version):

Beauty Dish Plate for all quick softboxes:

Cheetah Rolling Boom Stand

Cheetah Low Profile Bowens Mount for AD600, AD600 Pro, H600B, H1200B, S Bracket (with screw replacement) *select low profile option*

There's plenty of details in the video as well as my take on the difference, but I wanted to use an article as a place where people could view the images at their own speed.

Softbox Comparison

Quick SoupBowl QSB-26


Quick SoupBowl QSB-34


Quick SoupBowl QSB-42


MAX20 Parabolic


Quick RiceBowl QRB-36


Quick RiceBowl QRB-48


Softbox Accessory Comparison

Empty Softbox


Beauty Dish Only


Dish + Outer Diffusion + Grid


Dish + Double Diffusion + Grid


Double Diffusion + Grid 


Double Diffusion


Broncolor Siros 800 L vs. Profoto B1X vs. Godox AD600 Pro (AKA Xplor 600 Pro TTL)

Robert Hall

In 2016 I made a video comparing the Profoto B1 and Godox AD600. Since then both models have had an updated release and Broncolor has also released the Siros 800 and 400. I decided to put all three models head to head to help people decide which is the best option. I compare these 3 models because they are very high powered lights that feature an attached battery, remote power control, and all of the features that photographers look for in a strobe designed for location-based work.


I metered the 3 lights in the same indirect softbox (A Cheetah RB-90 with Chopstick mount accessory). This ensured no hotspots influenced the results and that the lights all had an identical spread of light leaving the softbox and hitting the light meter. The Broncolor Siros 800L is the champ when it comes to maximum light output. This isn’t a big surprise considering it’s 800w/s compared to the Godox’s 600w/s and B1X 500w/s. What is surprising is that it metered a full stop higher than the AD600, and 1.6 stops over the Profoto B1X. This goes to show watts aren’t a reliable figure of light output.

All 3 lights were very close to their listed “9 stop power range”. The AD600 Pro came in just below at 8.8, and the other two were slightly above 9 stops. They also all showed extremely stable outputs. The Broncolor Siros was the most stable but altogether the most the lights shifted the same power level was +-.1 stop. For the AD600 Pro and Profoto B1X these are big improvements, especially at their lower outputs. Also, it’s worth noting here that the Siros and B1X offer 1/10 stop control whereas the AD600 Pro only offers 1/3 stop increments.


Broncolor Siros 800 L vs. Profoto B1X vs. Godox AD600 Pro Power Comparison


One of the most popular uses of these portable monolights is High Speed Sync, or the ability to use flash beyond a camera’s max sync speed. The Broncolor uses HS, the B1X and 600 Pro use HSS. Technically, you can use HS with another trigger on the latter two, but I’m only addressing the native offerings. If you want to learn more about HSS vs. HS, here’s the best article explaining the difference. In short, HSS has visual consistency but decreased power, and HS lacks consistency but maintains peak power. Technically, you can use HS with another trigger on the latter two, but I’m only addressing the native controllers. Using the new Sekonic L-858D-U light meter which is capable of measuring HSS, I found the Profoto to be awful in HSS. At peak power the AD600 Pro only loses .9 stops in HSS, but the Profoto loses 3.2 stops! Considering the B1X is already the lowest light output of the three, this means it is quite ineffective for exceeding the sync speed in bright conditions.

Flash Durations

Another added capability of the Sekonic L-858D-U is that it can measure flash durations at any rate. I’ve always hated when companies market their products using t.5 flash durations, as they aren’t really a useful figure for freezing motion. T.5 represents the time that passes from a strobe’s peak output to 50% of it’s peak output, or one stop. T.1 represents the time between peak output and 10%, which is over 3 stops in light difference. The T.1 flash duration is a much better figure for determining whether or not the flash will freeze action.

Source :  Sekonic Blog

Source : Sekonic Blog

I’ve also questioned if Godox’s listed t.1 flash durations on the body of the AD600 Pro are even accurate. I ran all 3 lights through their entire range with t.1 figures and this is what I found.

Godox rounds up a fair bit. They market a shortest duration of 1/10,100 but in non-color mode (where the fastest speeds are attained) I could never get it to break 9000. The B1X performed really well, but the Broncolor crushed them both. I want to note here, when metering I found the figure would move as much as 1/200th of a second in either direction at the lower powers. I suggest you refer to these numbers as a ballpark figure. As I did with the last comparison, I plotted the flash durations against the power outputs so we could determine which light would have the shortest duration for a given output of light, rather than a power setting.

Flash durations mapped to light output

Flash durations mapped to light output

While the Profoto and Godox are pretty much neck and neck, the Broncolor Siros shines brighter using the cut-off technology in it's speed mode. Again, with the L-858D-U being the first meter to measure this figure, I can’t attest to the exact accuracy, although it seems pretty consistent with the manufacturer data.

Recycle time

At full power these all recycle quite fast.
Siros 800L - 2.7s

Profoto B1X - 1.9s
AD600 Pro - .9s

The AD600 Pro is the clear winner here. Even when I dropped the Siros down a full stop to match max output on the AD600 Pro, the Pro was still faster at recycling. The Godox also manages to recycle twice as fast while delivering more light than the Profoto. I tested all 3 beyond 50 pops and none showed signs of slowing down. The AD600 Pro has a limit of 100 full power flashes in quick succession before the thermal protection kicks in, or 50 full power flashes in HSS. The Profoto and Broncolor function as though the only limitation is their battery.

10 FPS

Never in my life have I considered shooting a strobe at 10 fps. But hell, you might. Since I just recently bought a Sony A7R III I switched to my Hi+ mode to enable 10 fps. I then pushed each light to see what full-stop power level I could sustain a long (15+ images) burst at.

Profoto B1X: 6.0 (1/16) light output F5.6 .1
Godox AD600 Pro: 1/16  or light output 5.6 .8
Broncolor Siros 800L: 5.0 Setting (1/32) or light output 5.6  .8

All of these could sustain a few images at a stop higher but would quickly fall behind. It’s ridiculous that all these lights managed to put out the this much power at such a fast rate.

Battery Life

B1X - 325 Full-power flashes, 1.5 Hour Recharge time (with 4.8A Charger)
AD600 Pro - 360 Full-power flashes, 2 hour recharge time
Siros 800 L - 220 Full-power flashes, 1.25 Hour recharge time

At first glance the Siros looks to be the worst performer, but it’s actually the best when scaled for output. If you brought it down to Godox output levels you would get well over 400 flashes. I can confirm the batteries recharge extremely fast.

Color Accuracy

I don’t have a color meter, so my test consisted of a white wall (Pure White, by BEHR) and correcting to neutral in Lightroom. I did keep all lights in their most stable color mode. That being said, all 3 lights had a 150K degree shift. I’m sure there would be more wiggle if there was an exact measurement because the color picker is limited to 50 degree intervals. Regardless, all 3 are extremely stable. If you want more scientific info on this, there is a Chinese video that meters all 3 and showed the Profoto B1X was the least stable for color, but the contest was very close.

When flipping to HSS, color is still just as important. Strobes typically experience more wild color swings in this mode. The AD600 Pro had a 450K shift and required a tint correction of -9, so it’s a little magenta. The B1X has only a 300K shift, but needed tint corrections from -30 to -50. Personally I would rather have the increased white balance drift over the magenta cast because balancing that tint in daylight would result in backgrounds with a green color cast. The Broncolor will carry better color over to the HS system because it’s not altering the pulse of the flash.

Color Comparison between Siros, B1X, and AD600 Pro

Color Comparison between Siros, B1X, and AD600 Pro


Of the 3, the Broncolor Siros is the only one that doesn’t offer TTL. Both the Profoto B1X and AD600 Pro also have a feature that converts a TTL setting to manual for continued shooting without a preflash.

Build Quality

The prices perfectly fit the build here. The Siros is an absolute tank, weighing in at 9.5 lbs. The only part that isn’t completely solid is the fan vents which are still heavily reinforced. The only odd thing is that the control knob on the back display protrudes beyond the edge. So if it landed back first there’s a chance that control knob would take some impact. The Profoto on the other hand recessed both ends of the light. While it’s great for the back, I criticize the choice for the front bulb because it not omnidirectional. This means it’s less able to fill a softbox and create maximum directions of light from a softbox. I find this to be the biggest oversight of the B1 series, but it does offer substantial protection. While Godox did their best to copy the style of the Broncolor Siros 800, they missed the mark with the location of their display. Now that I’ve smashed a few AD200’s, I realize what a liability it is to have the display and controls without a protective bumper. Even minor falls can kill your display and make it complete guesswork to sync a trigger to the light. Despite the Profoto B1X having a superior build quality, it’s still fairly light at 6.25 lbs, compared to the 7.5 lb AD600 Pro.

My broken AD200 display after a light stand tip onto desert ground.

My broken AD200 display after a light stand tip onto desert ground.

Modeling lamps

The Siros and B1X both have tungsten-colored LED lamps for a traditional modeling lamp experience. The AD600 Pro has the brightest LED and it’s daylight balanced. You can however focus the Profoto LED into a pretty tight beam using the stock reflector and get close to the brightness of the AD600 Pro. I also found the pattern of the Profoto’s lamp to be the most even of the 3. I feel the LED’s on all 3 toe the line of being potentially useful in close proximity indoors, and completely useless in daylight.

An LED comparison of the Profoto B1X, Broncolor Siros 800 L, and Godox AD600 Pro at 100%

An LED comparison of the Profoto B1X, Broncolor Siros 800 L, and Godox AD600 Pro at 100%


The X-Pro from Godox has a large display and plenty of functionality, but is tough to see in daylight. It is limited to 5 groups, and is capable of triggering a massive list of lighting products. One advantage it has over the other two is that you always see the power settings of your lights, so you know exactly where you are in the range. The other two just let you adjust a group rather than see the current power setting.

I felt like the Profoto Air Remote was the most responsive and simple trigger of the 3. The display is the best for reading outdoors. It will trigger any light in the “air” series. It is limited to three groups though.

The Broncolor RFS 2.2 is the same exact body as the previous X1 trigger from Godox. Broncolor worked directly with Godox to adapt this trigger to their Siros lights, and to optimize the HS capabilities. While you can control up to 40 different lights with it, it was the slowest to control. There is the BronControl app that offers full control of their lighting as well that makes for a great alternative in a fixed environment.


Broncolor and Profoto offer pack and head systems that are simply a higher class of lighting than offered by Godox. Godox offers a robust lineup of smaller lighting tools, from speedlights and hybrid strobes like the popular AD200 that all work seamlessly alongside the AD600 Pro. I think the system offerings from Godox are much better suited to event and session based photography, such as weddings and portraiture. The system offerings from Broncolor like the Scoros are some of the best options for high end product and commercial photography.

Profoto does offer the A1 and B2 which could work great for events and run-and-gun photography, as well as high end pack systems for commercial work. All 3 have impressive ecosystems that work together and are worth exploring before commiting to a specific brand.

Gels and Modifiers

For the most part, the discussion about modifiers is pointless. Broncolor offers incredible paras, but they are also easy to switch to Bowens mount and use with the AD600 Pro. Alternatively you could mount a Siros onto a cheap eBay softbox. All 3 have popular mounts that modifier companies offer. Profoto has the most elegant gel and grid solution, since they attach directly to the head and do not require a reflector. I also see an advantage with the design of the B1X considering you can zoom any of their softboxes or reflectors to control the spread of light. However I find it silly that the head is not omnidirectional.

Profoto B1X with OCF Grid

Profoto B1X with OCF Grid

A comparison between the spreads with and without their reflectors

A comparison between the spreads with and without their reflectors

Service / Global Use

Godox is only in its third year of being heavily adopted by photographers. One of the biggest perks of choosing Profoto or Broncolor is their global availability from rental companies. So if you regularly travel for work and rent gear you’re better offer becoming familiar with those two brands of lighting.

Price and Value

AD600 Pro / XPro remote -  $899 / $69
Profoto B1X / Air remote - $2095 / $419
Broncolor Siros / RFS 2.2 - $2237 / $112

When including the very high priced remote, the B1X is the most expensive of the 3. The AD600 is unsurprisingly the cheapest of the lights. Godox has risen in popularity strictly because of the performance offered at their low pricing. I think it also has the best value because it competes so well across all categories and features.



In conclusion, I can’t peg any light as the best since they all win different categories that photographers will place emphasis on depending on their needs. If you value output the most the Siros is the best option. The controller experience or modifier control may have you choose the Profoto B1X. If you are trying to get very capable lighting without spending a ton, the Godox AD600 Pro fits the bill.

One thing is abundantly clear to me. No longer can we blindly consider a brand to be the best choice simply because it was the best before.

The Sony A7 III is the Biggest Steal in Full Frame Cameras

Robert Hall

I was thumbing through my phone during a break at the WPPI expo in Las Vegas when I came across the news that the Sony A7 III had been announced. I was very interested considering I had just switched from Nikon to Sony, starting out with the new A7R III

While I'm thrilled with the switch, one thing I was unsure about was using such a high megapixel body for a high volume workflow. While I was aware the next iteration of the A7 may be a better fit for me, I had to switch during the winter months before my year started picking up. I first read the price, at just under $2000.00 I knew there had to be a significant compromise. I assumed it would have a single card slot, the smaller battery, or maybe have a weaker autofocus system than it's "bigger" brothers.



Sony A7 III specs

Camera Format    Full-Frame
Pixels    Actual: 25.3 Megapixel
Effective: 24.2 Megapixel
Max Resolution    24 MP: 6000 x 4000
693-Point Hybrid AF System
15 stops of dynamic range
UHD 4K30p Video with HLG & S-Log3 Gammas
2.36m-Dot Tru-Finder OLED EVF
3.0" 922k-Dot Tilting Touchscreen LCD
5-Axis SteadyShot INSIDE Stabilization
ISO 204800 (51200 native) and 10 fps Shooting
Built-In Wi-Fi and NFC, Dual SD Slots
USB Type-C Port, Weather-Sealed Design
Battery    1 x NP-FZ100 Rechargeable Lithium-Ion Battery Pack, 7.2 VDC, 2280 mAh
Sensor Type / Size    CMOS, 35.6 x 23.8 mm
Dual SDHC / SDXC card slots
Weight    1.43 lb / 650 g


In case you missed it in the spec sheet, here's the best part:

"An evolved 4D FOCUS system now employs a combination of 693 phase-detection points, which cover approximately 93% of the frame, along with 425 contrast-detection areas for reliable and quick autofocus and subject tracking performance."

693...recognize that number? You should, it's the same AF system as the $4,498.00 Sony A9 released last year.

So Sony took the amazing AF system of the A9, and the 15 stop dynamic range of the A7R III, brought along the dual card slots and larger battery, and packaged it for $1998.00. The ONLY downfall that I can find with this camera is that it won't share the incredible viewfinder experience of the A9. So expect a bit more blackout time. Beyond that, this camera is unbelievable.


I rushed to the packed Sony booth the following day. In less than 5 minutes hands on I was placing my pre-order (only to find out it couldn't go through until midnight). 

In the past I've always used 2 of the identical camera bodies. I want to be "in sync" with a body as much as possible, never spending valuable time searching for controls as they differ between bodies. I've built that belief after years of using Nikon cameras that had minute control changes with every single release.  However, the A7 III has the identical body as the A7R III. Pair that with the customization and the only difference in handling the two will be how the AF points line up.

I feel the A7 III is 2018's D750. It offers an insane level of performance at an affordable price. I'm sure there's a lot of aggravated A9 and A7R III owners out there. One negative of buying into Sony is your camera investment can quickly be devalued by their fast-paced innovation (and refreshing bodies when they should be recalling them - I'm looking at you A6300). I think this move is Sony's bold method of grabbing as much market share as possible before Nikon and Canon move into the full frame mirrorless market. It seems like they are almost losing money on this body, but I'm sure they'll make it up on the lenses.

The Sony A7 III will be available April 10th, 2018 and can be purchased here

Godox Wistro AD600 BM Unboxing and Overview

Robert Hall

Unboxing and Overview of the Godox Wistro AD600 (Bowens Mount)


  • Powerful 600Ws
  • Fan Cooled
  • 10W LED Modelling Light (Adjustable)
  • Optional Remote Head (600Ws & 1200Ws Options)
  • Godox and Bowens mount versions available.
  • Built in (removable) 11.1V / 8700mAh Lithium-ion Battery
  • Up to 500 Full Power Pops Per Battery Charge
  • 0.01 – 2.5 Seconds Recycle Time
  • Flash Modes – TTL / M / Multi ( There is a version with TTL and one without TTL)
  • HSS to 1/8000th
  • Second Curtain Sync
  • FEC / FEB – 1/3rd Increments (±3 Stops)
  • FEL (Flash Exposure Lock)
  • Manual Flash – 1/256 – 1/1 Output (1/3rd Increments)
  • Godox 2.4GHz X Radio System
  • ETTL & ITTL Radio Slave Modes (Auto Switching)
  • Range – 100m + with X1 as Transmitter
  • Groups – A / B / C
  • 32 Channels
  • Supports Legacy Godox FT-16 Remote Manual Trigger System
  • Supports Godox XT-16 Remote Manual Trigger System
  • Canon & Nikon Optic Wireless Slave Modes
  • Groups – A / B / C
  • 4 Channels
  • S1 & S2 Optic Slave Modes
  • Up to 500 Full Power Flashes
  • 0.01 – 2.5 Seconds Recycle Time
  • Flash Duration – 1/220s-1/10000s
  • Large Dot Matrix LCD Display
  • Custom Functions
  • Auto Memory Function
  • Micro USB Port for Firmware Upgrades
  • USB Communication Port (For FTR-16 & XTR-16 Receivers)
  • 3.5mm Sync Port

    MODELAD600 (Godox Mount) / AD600B (Bowens Mount) 

    Wireless slave mode*Radio transmission mode (compatible with Nikon & Canon)*Optical transmission mode (compatible with Nikon & Canon)

    Flash modeLocalM/Multi

    2.4G slave modeTTL/ M/Multi

    Optic slave modeTTL/ M/Multi

    Slave unit compatible cameraNikon  i-TTL/M/RTP flash(master unit uses TTL wireless flash trigger X1N etc)Canon EOS E-TTL II/M/Multiflash(master unit uses TTL wireless flash trigger  X1C etc)

    GN ( 1/1)87 (m ISO 100, with AD-R7 standard reflector)

    Flash duration1/220s-1/10000s


    Power control9 steps:1/256~1/1

    Multi flash√(times:100 times;frequency:100)

    Flash exposure compensation(FEC)manual,FEB:±3 stops in 1/3 increments

    Flash syncHSS(1/8000s),first curtain sync,second curtain sync

    Flash delay0.1~10s



    Modeling lamp(LED)10W

    Optic slave flashS1/S2

    ScreenDot matrix LCD screen

    WIRELESS(Optic and 2.4G

    Wireless flash functionslave,off

    Controllable slave groups5 groups:A, B, C, D, E

    DistanceOpticindoor:12~15m/39.4~49.2 feet outdoor:8~10m/26.2~32.8 feet


    ChannelOptic4 groups:1, 2, 3, 4

    2.4G32 groups:1~32



    Full power flash times500 times

    Recycling time0.01s-2.5s

    Power status√

    Power savingPower off automatically after 1 hour’s none operation

    Triggering mode3.5mm port,PC port,wireless remote port

    Color temperature5600±200k

    Size220*245*125mm (flash tube & reflector not included)

    Weight 2.66Kg (flash tube & reflector not included) Aprox. 2.9KG total


Nikon D810 Review and sample raw images

Robert Hall


Nikon d810 raw samples -small raw and full size .NEF files

Review of Nikon D810

Nikon's newest dSLR has challenged many buyers. While it boasts excellent build quality, a phenomenal sensor with the best dynamic range ever recorded, and superb low-light performance, many are left worrying that the gargantuan file sizes will hinder their workflow or find the high megapixels unnecessary to begin with.

So what's all the hype about, and is this camera right for you?

For starters, the camera's sensor and processor are about as good as it gets in the world of dSLRs. It can reach up to a class-leading 14.8 stops of dynamic range. It is powered by the EXPEED 4 processor that Nikon uses to power it's flagship D4S. And it is first dSLR to have the Optical Low-Pass filter removed completely (The Nikon D800E and D7100 both had a reduced OLPF for sharper images) resulting in the sharpest images possible from a modern dSLR. 

Click here for full specs of the Nikon D810

The D810 has many minor tweaks that make it a much better option than its predecessors, including:

- A shutter that is substantially quieter than previous models and other professional dSLRs.

- A lower base ISO of 64, 2/3rd 's of a stop lower than most cameras. It also has an expandable ISO range on the bottom end, going down to 32 at L 1.0

- Increased to 5 fps, and faster in reduced quality modes, or with the MB-D12 battery grip

- Small Raw - Nikon has taken a much desired aspect from Canon and implemented it into the Nikon D810. You can now get a 9 megapixel raw image. With the option of crop modes, you can even get various other sizes of raw images.

-Brighter OLED viewfinder

-Auto-ISO in video mode

-Group AF mode, in which you control 5 points at once to give a wider area to auto-focus on while still controlling the position.

There are many other tweaks made that make the D810 a far superior camera to the d800 and d800E family. There have been some reports that the body is even better than the d4s, when sharpness and recoverability are considered. I did my own test using both the full size RAW .NEF files, and the 9 megapixel small raw option. While the small raw is certainly a much better option than jpeg, it does not hold a candle to the full size .NEF files. Comparison table below.

D810 Full-size RAW recovery on underexposed image



recovered 5 stops

recovered 5 stops

D810 Full size RAW recovery on overexposed image



recovered 4 stops

recovered 4 stops

D810 Small size RAW recovery on underexposed image

original underexposed small raw file

original underexposed small raw file



D810 small size RAW recovery on overexposed image



attempted recovery

attempted recovery

As you can tell, the full size .NEF file is still the way to go to ensure you can recover as many details from clipped highlights and shadows as possible.

Overall, the Nikon D810 has fixed everything about the overzealous D800 and D800E. The EXPEED-3 processor was just not enough to handle the high file sizes. On the Nikon D810, you don't even realize the size of your files because the EXPEED-4 processor handles them so well (until you have to copy and edit them that is). Simple things like the viewfinder improvements, lower base ISO, better high ISO performance, group-AF, quieter shutter, all make this camera a tremendous upgrade. The complete removal of the OLPF leads to the sharpest images imaginable from a dSLR. After reviewing files from both systems, I can confidently say that the d810 has completely separated itself from the Canon 5d Mark III.

Here is a dropbox link to sample D810 Raw sample files if you would like to play with any full size images yourself.

Feel free to share with any friends or photography groups that you think may find this helpful, including the drop box link.

Thanks for reading, comment below if you have any questions!




What do the F-stop Numbers Represent?

Robert Hall

An explanation of the mathematics behind the F-stop

When making the jump to manual photography, one of the most confusing topics can be that of the f-stop. Even after learning that the aperture controls your depth of field, you can still be very confused by why the numbers change the way they do. It's no surprise, as circle geometry isn't something you use in your daily life.

However, understanding the mathematics can give you an excellent grip on the f stop scale, especially if you're the left-brain type. Let's assume that you are already familiar with the full f-stop scale (1.4 - 2 - 2.8 - 4 - 5.6 - 8 - 11 - 16 etc.). Why is it that only increasing .6 from 1.4 to 2 is the same time of adjustment as moving 5 from 11 to 16?



The reason is that the f/stop number is actually a ratio between the diameter and focal length of the lens. The inverse relation of light stems from the diameter becoming smaller as the f/stop number increases. For instance, an 85mm lens at f/2 will yield a diameter of 42.5mm (85 / 2), If you stop down (increase the f/stop and reducing the light 1 stop) to f/2.8, the diameter is now  30.3 (85 / 2.8). Now I know what you are thinking, 30 isn't half of 43, so how did we halve the light if the diameter didn't get cut in half?

This brings us back to circle geometry. We need to look at the area of light that passes through the opening. The area of a circle is found by π x radius^2. The radius is half of the diameter, and pi is a constant that represents the circumference divided by the diameter. So, lets do the area math for the example above with the 85mm lens.

At F/2 we have a diameter of 42.5, and F/2.8 is 30.3. This gives us a radius of 21.25 and 15.15 respectively. 

So for f/2 we have π x 21.25^2 = 3.14 x 451.5 = 1418 square mm (rounded)
For f/2.8, its π x 15.15^2 = 3.14 x 229.5 = 720 square mm (rounded)

As you can see (while looking past some rounding), we have reduced the area of the opening by half. This is why when you increase the F/stop number  by one stop and reduce the size of the opening, you are reducing the amount of light that can get through by half. The ratio also explains while the numbers start to have bigger intervals as you move up the scale.


Hope this helps and please feel free to keep asking questions so I can provide you with more educational content!

Robert Hall is a professional photographer in Southeast Michigan. His work primarily consists of weddings, commercial and editorial. He is constantly improving his skills through discussion of techniques and critique with fellow photographers. Robert is always looking for new connections on social networks!
Twitter / Instagram: @robhallphoto