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 14 of 39
A Quick Look at the New Sigma 24-35 f/2 Art
* Image Courtesy Sigma USA * I generally do MTF testing on multiple copies of a given lens so that I can present the averages, look at sample variation, and stuff like that. I’m always aware that looking at any single copy of a lens, especially a zoom lens, gives only a limited prediction of how…
24-70 f/2.8 Zoom MTF and Variation
We’ve finished, mostly, our fairly long series of articles on SLR prime lens variation. We started with prime lenses for several reasons. They are much quicker (and quicker is a relative term here) to test than zooms. They are simpler lenses and we expected that meant they would have less…
Supertelephoto MTF Curves
Brandon has accomplished much during his summer with us, including several things I never thought we’d be able to do. One of those things was measuring the MTF of supertelephoto lenses on our optical bench. A vertical bench just isn’t designed to handle the mass of those big lenses and technically…
Variation Measurements for Telephoto Lenses
We’re nearing the end of the Varation series for prime lenses. If you are joining in late, you may want to go back to the original article for an introduction into the methods used. Today will look at the short telephoto group, lenses ranging in focal length from 85mm to 150mm. We’ve also included…
Variation Measurements for Wide-Angle Lenses
When we started this series, we introduced our methods using 24mm lenses, then followed up with looks at the 50mm and 35mm groups. Today we’re going to go back to the wide-angle lenses; the ones we expect to have the most variation of all. We probably should call this post the Zeiss Invitational,…
Variance Measurement for 35mm SLR Lenses
Last week we posted optical bench MTF and copy-to-copy variation measurements for 50mm SLR lenses. We’re going to continue that series this week with the same measurements for the 35mm lenses. This set should fill out the wide-to-standard range lenses and gives us a lot of interesting data as we…
Variation Measurement for 50mm SLR Lenses
Last week we posted an introductory article on how we measure copy-to-copy variation in different lenses. I’ll be continuing to publish these results over the next few weeks for prime lenses. We will eventually have a database put up, but I think it’s important to look at the different lenses in…
Measuring Lens Variance
Warning: This is a Geek Level 3 article. If you aren’t into that kind of thing, go take some pictures. I’ve been writing and discussing the copy-to-copy variation that inevitably occurs in lenses since 2008. (1,2,3,4) Many people don’t want to hear about it. Manufacturers don’t want to acknowledge…
Canon 5Ds Teardown
When Lensrentals.com first got the first Canon 5Ds and 5D sr cameras in stock, Aaron and I immediately started screaming that we wanted to take one apart. It turns out we received enough 5Ds cameras to let us have a day with one to do just that. Of course, we don’t expect to find out anything…
Canon 5DS and 5DS R Initial Resolution Tests
Like everybody else, we’re pretty excited to get our hands on Canon’s new 5DS and 5DS R. There are already a lot of hands-on articles about the cameras that probably have told you more than you need to know to make your purchase decision. Of course, for most of the Canon shooters who read this…
I Don’t Know Why It Swallowed a Fly – Weather Sealed Lens With a Fly Inside
I’ve been blogging about testing and taking apart camera equipment for almost a decade. Lensrentals.com has many thousand lenses these days, and they all get used frequently. When you have lots of lenses and they get used frequently, stuff gets inside them. Usually the stuff that gets inside is…
The Space Lens Mystery Screw
We get to do some fun things through our testing company, Olaf Optical Testing. A lot of it I can’t talk about but sometimes we get a project that we can share. One of these came up recently when Matt Leeg asked us if we were interested in testing and cleaning an Angenieux 25mm f/0.95 lens that was…