Lens aperture, f-stop and why it’s intuitive

There are a lot of beginners in photography who don’t fully understand lens basics. It’s a lot to take in, especially if you aren’t mathematically inclined, so there’s no shame in that. I also think experts in photography get a little confused by the digits and pass that along to beginners. As a demonstration, I typed “explain lenses to me” in Google and one of the top articles I was linked to is published at masterclass.com. It’s a great article, and the majority of it is accurate but I spotted a mistake.

You’ve probably read or seen a million and one articles/videos about lens basics, but I think the way I view it is different to those. Please let me know what you think in the comments below as I don’t want to churn out content exactly the same as everyone else :).

F-stops are counterintuitive, because the larger the number, the smaller the opening

This is a quote from the article, and you might think it’s accurate, right? That’s actually wrong; the bigger the aperture, the bigger the number. Aperture values aren’t expressed like ISO with a simple number e.g. 100, 200, 400, etc. They’re a calculation/ratio/equation: f/x. F (the focal length of the lens you have mounted e.g. 100mm) divided by (the slash) a value (e.g. 1.4). If you don’t complete the calculation and you only take digits from an equation, it will seem counter-intuitive.

Aperture values are expressed as a calculation/ratio/equation

A bigger aperture gives you more background blur when all else is equal; consequently, a bigger aperture number gives you more background blur as well. They are one and the same but not if you misunderstand the calculation. It’s intuitive when you realise you’re given a calculation and not a number.

Using two example apertures, both with a 100mm lens, we can calculate dimensions… For my first two examples, I will use f/1.4 and f/2.8, where f = 100mm:

  • 100mm / 1.4 = 71.4285714286mm (this is your aperture when expressed as a number i.e. a dimension, NOT 1.4; 1.4 is simply a VALUE from the equation).
  • 100mm / 2.8 = 35.7142857143mm.

As you can see, the bigger diameter/number (71.4285714286mm) is the wider aperture and gives more background blur (all else being equal).

Why have aperture expressed as an equation rather than a dimension/number?

A number on its own would soon become confusing. Let’s pretend we have a 35mm lens mounted; f = 35mm:

  • 35mm / 1.4 = 25mm.
  • 35mm / 2.8 = 12.5mm.

A 12.5mm aperture on a 35mm lens is the same as 35.7142857143mm on a 100mm lens. As you can see, it’s awfully confusing. So it’s a lot easier to have f/2.8 shown in camera. The bigger number is f/1.4 — not f/2.8.

Sony a7r IV vs the Sony a7rII — comparison review

The Sony a7r IV has been announced, and it looks like a really awesome camera. Unfortunately, I cannot afford one for a long time but I will be buying one at some point and I’ll most likely keep the Sony a7rII as a backup camera. If I could get one before I fly to Canada next year, that would be awesome.

I’m doing a bit of a Sony a7r IV vs Sony a7rII spec sheet comparison review for myself because that’s what I’m interested in; I figure I’d share my findings with you :).

Sony A7r IV vs Sony a7rII Comparison Review

Sony a7r IV:

  • 61 Megapixels
  • Shoots 10 FPS
  • 15 Stops of Dynamic Range
    Improved low light performance
  • The sensor is ever so slightly smaller at 35.7×23.8mm vs 35.9 x 24.0mm in the Sony a7rII
  • Eye-autofocus, video and stills and lots of focus improvements
  • Viewfinder; UXGA (1600 x 1200px) OLED; 5 760 000 dots, approx. 0.78 x magnification
  • LCD; 7.5cm (3.0-type) type TFT; 1,440,000 dots; touch screen
  • Playmemories Camera Apps™ – No
  • Weight; Approx. 665g / 1lb 7.5oz (with battery and media)
  • Dimensions (W X H X D); approx. 128.9 x 96.4 x 77.5mm. Approx. 128.9 x 96.4 x 67.3mm (from grip to monitor)
  • Better sealing
  • Dual Card Slots
  • Bluetooth remote
  • FTP Transfer / wireless tethering
  • 5ghz WiFi

Sony a7rII:

  • 42.4 Megapixels
  • Shoots 5 FPS
  • Type Tilt type 2.95″ (3.0-type) TFT drive, approx. 1,228,800 dots
  • Viewfinder; XGA (1024 x 768px) OLED; 2 359 296 dots, approx. 0.78 x magnification
  • LCD; 3.0″ type TFT LCD; 1,228,800 dots
  • Playmemories Camera Apps™ – Yes
  • Weight; 582g (Body Only) / 625g (With battery and media)
  • Dimensions (W X H X D); approx. 126.9 x 95.7 x 60.3 mm
  • Single Card Slot

Design compliments

There’s many obvious differences compared to the Sony a7rII and those differences are less obvious if you have the Sony a7rIII. I appreciate the improved viewfinder, sealing against moisture, etc. Together, these make up a pretty massive upgrade for me. The viewfinder and sealing alone is reason for me to pick the Sony a7r IV over the Sony a7rIII.

Not too many years ago, people were saying six frames is more than enough for action photography. It’s interesting how perceptions have changed. I might make use of the high shooting rate when I photograph bears. It hasn’t been important to me in the past but I hadn’t photographed many moving subjects before either. I have a vision of what I want to photograph travelling next year and as such I think this would be useful to me.

I’ve been backing up my photographs using my phone, but I appreciate the dual card slots as well. I often use the WiFi feature for photographing inside a house. It’s got its limitations, such as not being able to bracket properly — this makes no sense at all. FTP is standard in file transfer and I will find really useful. If I bought a cheap laptop/tablet, I could bring it with me for interior photography and shoot tethered — pretty cool! I am curious to do speed tests and whatnot of the FTP and see if remote shooting with the phone has improved.

The little button on top of the exposure compensation dial scared the crap out of me but luckily it’s a toggle button. You press it and it’s locked; press it again and it’s unlocked or vice versa. If you don’t like it, just leave it unlocked.

The grip looks more comfortable but I’m not 100% sure how it will be. I have huge hands. I’ll wait and see…

The sensor looks to be better in every regard. There is one caveat with this, but I will talk about that in the complaint section of this article. From what I can make out so far, from specifications and whatnot, you’re not getting extra megapixels at the cost of low light performance or something like that. I find more megapixels helps for fancy edits, plus noise is actually reduced when you down-sample, due to the signal to noise ratio.

The menu is superior to the Sony a7rII. I’ve memorised the menu with my Sony a7rII, but for those who haven’t… Good luck. More on that in the complaint section… You can now SAVE the menu and transfer it to another camera. Good job Sony. It would be nice if you could customise the entire menu on your computer and reconfigure everything.

I’m going to congratulate Sony for not including a pop-up flash or something stupid like that. There are people who craze for this feature. If you see a little bulb, there also has to be a capacitor to power it, so I’m glad there’s no flash.

I’m also going to congratulate them for having two SD cards and not one SD and one compact flash or something crazy.

I might genuinely make use of the video features this time around. I’m pretty clueless with video, but being able to record great videos in automatic mode makes me happy, haha.

Complaints with the Sony a7r IV

I’m starting to wonder about my own personality, because after watching all of the Sony a7r IV related videos on YouTube, I thought of a few gripes with the camera.

The price, here in the UK, is a bit of a kick in the face. I bought my Sony a7rII for £2,600. This is £3,500. I bought the camera expecting replacement, newer generations, to be about the same. Sony has always dropped the prices on their products quite drastically after a short time; I guess they don’t like to reward early buyers at all (lol), so even if I had the funds to buy it right now… I think I’d want to wait a bit. I find this entire pricing strategy an insult to loyal users who buy new products.

It’s a £3,500 camera and if you’re not satisfied with it but you’re tied into Sony, you’re semi-stuffed (that goes for all brands), so good job Sony;  rather than potentially having my money now, you’ll have to wait for it.

No lossless compressed raw

The bump in megapixels is nice; I’m always in favour of technical advancements. However, I would like to see an mRAW function and it is not in the menus. Additionally, a LOSSLESS compressed raw option. I know Sony has LOSSY compressed; but true lossless should not impact the data. If you don’t understand the code and whatnot, consider it like a rar file.

I imagine you’ll get about 8 shots per gigabyte. 80, 10 gb; 800, 100 gb; 8000, 1 tb. 8,000 * 6 tb = 48,000 shots on a 6tb drive.

48,000 / 100 = 480 days at 100 shots per day. 6tb * 3 (triple redundancy) = about £600.

£456.249999996 per year in storage costs at 100 shots per day with triple redundancy, unless I have calculated it completely incorrectly.

The buttons, user interface and menus

I noticed in the videos people are asking about the dial on top on the camera. This I found, really, really weird. Do reviewers not use their cameras much then? It’s just the same dial as before but put on top of the frame. Originally I thought it looked hideous, and I do still think it looks a little worse but it’s not that bad when you look at it from other angles. I will reserve judgement until I see it in person. Maybe it allowed for superior sealing, easier replacement if it breaks or more space in the body. Who knows? At the moment, it’s more caution rather than a negative for me.

The top left side of the camera is unused but the top right is basically cramped. The PASM dial cannot be user defined to something else nor can the exposure compensation dial. The dials you can configure, you don’t really want to because you’ll want them for your shutter and aperture settings. Personally I would have liked to see the PASM and exposure compensation dial user customisable, and an OLED on the top left of the frame. You might even be able to remove one of the dials but have the same functionality, with an OLED. Failing that, do what the Sony a9 does and have a dial on the top left.

The menu-interface… I know some devout Sony fans will argue (I’ve seen it on dpreview, lol) I’ve never used a Sony camera (I’ve had the Sony a7rII two days before it officially hit the shops, I believe), I’m just not used to it or whatnot… but damn it’s bad. To switch picture profiles, enable APS-C mode for video, etc. etc. requires unnecessary button pushes. They still haven’t separated a lot of the stills functions from video! And if you’re like me and you want to dabble in video but you don’t want to keep changing settings around, it’s a nuisance.

The labelling on my Sony a7rII reminds me of going into a shop, and the aisle that says “milk” has eggs. You’ll get used to it. You’ll remember it even, but it truly doesn’t make any sense.

I would have liked to have seen a much improved user-interface and a touch screen to flick through the menu better. I believe they can still implement it. I’d probably code it for free if they let me.

Screen

The screen on the back looks cheap. I would prefer it to be an OLED with gorilla glass and a proper hinge mechanism, even an old point and shoot Canon G5 has a better hinge mechanism. I’m curious how sealed against moisture it is too.

Memory Cards

What would be cool is if you could have alternate writing e.g. shot 1 goes to card one, shot 2 goes to card two, shot 3 goes to card one, shot 4 goes to card two, and so on. This would improve writing speed if desired.

Accessories

There should be a small, cheap, bluetooth GPS chip that tethers with the camera. I am not saying have that as part of the camera, but it should be a separate accessory. I’m comfortable using my watch but Sony should try tackle the GPS situation somewhat at least. If they do make such a thing, they will probably charge more than a Garmin Fenix 5x Plus smartwatch (lol) but hopefully they will be realistic; £100 is acceptable for convenience.

PC Sync Port

The PC Sync Port is absolutely unnecessary in my opinion. It looks hideous and I’d have preferred to have seen something more exciting.

Conclusion

It seems like a lot of people are left feeling the Sony a7r IV is not as exciting as previous releases. I’m glad I wasn’t the only one to feel that way. However, maybe we were all expecting too much. After about a day of this sinking in, I’ve began to think that it’s probably a lot better than what we give it credit for. Nothing was too broken with the Sony a7rIII compared to the original Sony a7r either. The more I’ve been thinking about the features though, the more I release they’ve added things I’d genuinely make use of e.g. better viewfinder, FTP, etc.

I can put up with the menu problems, and the cramped top might not be a problem in real world use (it might not look as ugly either). Storage is getting cheaper too. I will feel a bit more assured climbing mountains with a more sealed camera, and I find the improvements important to me. I truly think that it looks like an amazing camera but I think Sony got a little lazy too! That said, most of my complaints stem from a user interface / button layout perspective; its performance looks amazing.

The Sony a7r IV looks like a great camera though and it looks like it’s almost perfect for me :).

Canadian Trip, Models, & Photography Stuff

Hey,

Recently a photographer in the YouTube community has been accused of various nefarious deeds. It’s made me wonder about certain things and where I should go with photography :).

I want my website to offer the odd bit of information for people, in the future. And eventually I think I’d like to travel blog more with it — that was its original intention.

The theme itself kind of sucks. I’ve been patching it here and there but it’s kind of like putting duck tape on an axe wound — if anyone knows of any good themes, let me know! In some ways, I can see why people go towards sites like squarespace because they make things simple. They’re quite expensive though.

Last year I regretted not buying a keyboard and writing a kind of travel diary. I should have taken more photographs too. That said, it was a bit of a learning experience for me and now I am really excited for next year! I’d go this year, but to be blunt, I cannot afford it.

And on the topic of money… I’m thinking of selling my Zeiss Loxia 21mm f/2.8 lens. It is an incredible lens, so it’s not that I have anything against it. The Sony 16-35mm f/2.8 GM lens I own covers the focal length and aperture. It’s not as nice feeling, the sunstars aren’t as good and its flaring control isn’t as good but I have to be realistic, I think that money could be better spent on a 70-200mm f/2.8 GM lens or even a 100-400mm f/4.5-5.6 GM lens. That way, I’d be able to photograph lots of wildlife when I travel next year.

Lastly, also somewhat related to the Jason Lanier controversy is shooting models. I guess it’s made me think that there are a lot of questionable characters taking photographs of people even if he, himself might be innocent. I think I’d like to try it more, and I have some friends in Canada who said they’d let me photograph them :). So I’m kind of undecided if I’ll get an 85mm, 135mm, 70-200mm or the 100-400mm. I’ll see how funding goes, I guess. I still have a year to decide, so there’s no rush.

Basically this is a post about nothing really, haha. It’s just some thoughts running through my head.

 

 

Dell XPS 15″ OLED and 100% Adobe RGB, 144hz monitors

Dell now let’s you order their Dell XPS 15″ Laptop with an OLED screen. I’m not buying one (they’re too expensive for me), but it’s nice to finally see OLED’s make their way into devices bigger than a phone.

If anyone knows of a 24 inch 100% adobe RGB 144hz monitor, please leave a comment :). I haven’t seen any so far, but I would love one of those one day. I guess it’s just a matter of time now.

I’m not sure how Dell is addressing screen burn in but it would be kind of bad if the taskbar was stuck into the screen so to speak, haha.

Raspberry Pi 4 & flirc case

Hey,

I guess I’ve been living under a rock or something because I’ve only just noticed the Raspberry Pi 4 is available to order.

I own a Raspberry Pi 3b and it’s been quite useful to have. The Raspberry Pi 4  has faster networking facilities, a faster processor, USB 3 and it’s available in a 4G ram version! It looks pretty cool, plus you can get flirc cases for it now :).

I don’t know if anyone knows whether there will be a Raspberry pi 4 zero version of it? But that would be cool. You could make pretty fast file hubs / portable backup solutions with it.