Roger Cicala
I'm Roger and I am the founder of Lensrentals.com. Hailed as one of the optic nerds here, I enjoy shooting collimated light through 30X microscope objectives in my spare time. When I do take real pictures I like using something different: a Medium format, or Pentax K1, or a Sony RX1R.
Posts by Roger Cicala · page 7 of 39
Testing Lenses: Best Individual Focus MTF Curves
OK, in the last post we did something useful, but rather boring: we looked at how MTF changes when lenses are stopped down. Today we’re going to use a more powerful optical bench tool, the MTF vs. Field vs. Focus. Unless you work in a metrology lab (and probably not even then, very few are…
Testing Lenses: Stopped-Down MTF Curves
For quite a while now we’ve been publishing our MTF curves. They’ve always been the same thing; at least ten copies of each lens, in 4 rotations, and measured at the widest aperture. The reasons for that are (to us) very straightforward. Our purpose in doing the tests is to establish reasonable…
About Getting Your Camera Wet… Teardown of a Salty Sony A7sII
People think that because I expect the worst and try to prepare for it, that I’m negative. That’s not it at all. I’m not a negative person; I’m cheerfully cynical. If I expect the worst and it doesn’t happen, I’m happy because things went better than I expected. If I expect the worst and it does…
My Last Circular Polarizer Post
I posted an article about circular polarizing filters recently, letting you see some data I obtained for Lensrentals when they were reviewing which of the polarizing filters were among the best. I concluded that they all polarized light really well. I also said that none of the CPs I tested seemed…
The Extreme Batis: MTF Tests of the Zeiss Batis 18mm and 135mm f/2.8 Lenses
I’ve been slow to test the Batis lenses for several reasons. We can never get enough copies when they’re first released and by the time we do have enough copies I’ve got six other things to do. That said, I did give an overview of the Batis 25mm and 85mm a while back and even did a teardown of the…
The Minolta 40-80mm f/2.8 Gearbox Zoom; The Clockwork Lens
**There were giants in the earth in those days . . . They were mighty men, men of renown. _Genesis 6:4_** I’ve always been fascinated by the history of lenses. I write about it a lot. To me, the most fascinating items are those made many years ago, with what we would consider wholly inadequate…
Looking at Clear and UV Filter Spectrograms
I’ll start by saying, this is not an article – or at least not a complete one. When I wrote My Not Quite Complete Protective Filter Article, I promised to try to add transmission spectrograms so that you could see not just the wavelength I tested for transmission, but also how the rest of the light…
My Not Nearly Complete, But Rather Entertaining, Circular Polarizer Filter Article
So, a while back I wrote a not quite complete article on UV filters. To do that, I had to buy new testing equipment and learn to test filters. This was not what I wanted to do when I grew up. But somebody has to do it, and I did get to buy new toys. More importantly, Tyler (Who handles the…
Taking Apart the Sigma Cine 85mm T1.5 FF Lens
We’ve been impressed with the Sigma Cine lenses. We weren’t surprised that they’re generally sharper than classic Cine primes; that’s what we’ve come to expect from Sigma. We were pleasantly surprised by the smoothness of focusing and aperture and the apparent build quality. Since we’d previously…
Cine Lens Comparison: 35mm Full-Frame Primes
Good day! And welcome to our first Cine lens MTF comparison. If you aren’t familiar with what we do here, I suggest you take a glance at our previous post on why we’ve started testing Cine lenses. For those of you who haven’t been here before, let’s be clear about what this is not. It is not a lens…
Sony FE 16-35mm f/2.8 GM Sharpness Tests
Well, I’ll say to start with I’ve probably had more requests for the Sony FE 16-35mm f/2.8 GM MTF tests than any lens in recent memory. People are excited about it. About half the requests have been very reasonable “I’m hoping to see MTF results before I decide between this lens and that.” And, as…
Taking Apart the Zeiss 85mm T2.1 CP.3 Cinema Lens
Long ago, in an office far, far away we did a teardown of the Zeiss 85mm CP.2 lens. Since we’ve already seen the earlier model, we thought it would be interesting to take a peek inside the new Zeiss 85mm CP.3 lens as well. We’re going to have to work on them eventually, and it’s always good to have…