mdominic20

1 hour ago, Toby Cork said:

Hi everyone! Just getting into Diopters - sorry if these are dumb questions... 

I'm after a +0.5, and after reading everything it seems like:

Question 1) the Tokina AT-X MC closeup  and the Minolta 100-500 +0.5 are the way to go (yes?) - but super expensive! (Here's an example current ebay listing for $500: https://www.ebay.com/itm/tokina-achromatic-diopter-0-4-low-magnification-for-anamorphic-Isco-Kowa-Moller/173158037985?hash=item285105f9e1:g:LH0AAOSwqfZaWZ9x)

What about cheaper options? I can't find the ones that Tito lists in his guide (http://www.tferradans.com/blog/?p=7282)... 
Question 2) Is this the KENKO he refers to? https://www.amazon.com/Kenko-Close-Up-Lens-77mm-Multi-Coated/dp/B001CNC1RO/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1519155544&sr=1-1-catcorr&keywords=kenko+close-up+lens+77mm+mc+no.1
They don't list whether it's +0.5 on that page - it's super confusing. 

Question 3) Is this a good cheap option for a +0.5? Tamron 72mm Close-up Filter for 28-200/3.8-5.6 Zoom Lens, Product# FL71-400 https://www.amazon.com/gp/product/B00023JL1Y/ref=ox_sc_act_title_1?smid=ADP1I4ZKQNKOW&psc=1

Thanks in advance for any help you can give!

If you look a few posts above, you can see my comparison of the Tokina (+0.4) and Minolta (+0.33).  I found the Minolta on KEH for $45 shipped.  The Minolta is much cheaper than the Tokina, yet identical in quality (and possibly more versatile in range). 

I've been looking for a 72mm or 77mm +0.5 (does not need to be achromatic) for a little while, but they seem somewhat rare on ebay.  

i finally got a hold of a minolta 100-500 and compared directly it to my tokina 0.4.  setup was a gh4/contax zeiss 50mm @ f2.8/iscorama 36.  

tokina focus range: 3.8' to 8.9' (measured to the diopter)

minolta focus range: 4' to 10.5' (measured to the diopter)

field of view (at the same distance): minolta was about 1-2 degrees wider than the tokina. 

sharpness/overall image quality: identical

i was surpised that the tokina was able to focus that far out (seems like mine is closer to .37 than .40).  i was also surprised the minolta was able to stay sharp all the way down to 4'. 

so the minolta gives you another 1.5' of range at the far end, a slightly wider FOV (which is always handy), and you only lose a couple inches on the close end.  all things considered, i think i might be selling my tokina at some point.

I have a question about the popular (but hard to find) minolta close-up lens for 100-500...

some people say it's strength is 0.33, and others say it's 0.43.  no one seems to agree.

can anyone who owns one weigh in with some clarification?  

Thanks for the responses.  I ended up getting an Iscorama, because it made the most sense for what I'm looking for personally.  I also had a chance to test one out first, so I know I like the look.  Obviously the Kowa looks great too, and I have one that I'll use if the right project comes along.

As far as wide angles, I agree that a 37mm equivalent on FF is wide enough for 95% of shots I would need.  But on every project I inevitably find myself in a cramped interior space needing a 21 or 28mm lens in order to get a certain shot.  Small kitchens, cars, bathrooms, closets, etc.  An oval aperture mod/filter could defintely help those shots match a little better.  Is there a specific mod available for somethign like a Mir 10A, kind of like there is for the Helios?  Or is my best bet a generic filter I can attach?  If it's a filter with a black mask to create the oval, I think I might run into issues with vignetting on a lens that wide.

Here's some tips, based on my experience with the sharpness tweak:

I'm not sure if this is the case with every lens, but with mine, it was possible to adjust the sharpness without even removing the brass tabs.

Just by loosening all 6 screws, but leaving the tabs in place, it created enough rotational play in the front optic for me to fine-tune the sharpness. This is because the holes in the brass tabs are ever so slightly bigger than the screws, so you have a little room for rotation.  For me it was just enough. 

Once you find the sweet spot, simply re-tighten the screws.  No glue needed.  Be careful that the act of re-tightneing the screws doesn't nudge the optic. This took me a little while to get right.  Once everything is tight, check the image again to make sure it's still sharp.

As Tito says in his video, it's easiest to judge the sharpness using a long lens at (or near) infinity, and stopped down to 4 or 5.6.  In my case,  I could never get a sharp image with the Kowa and taking lens at infinity.  I had to focus both lenses slightly less than infinity to get a super sharp image. 

This is very important, especially if you are using a single-focus solution.  Don't blindly trust the infinity marks on your Kowa or your taking lens.  You might be able to get a MUCH sharper image by adjusting them slightly under infinity.  I'm sure this will vary from lens to lens.

Hopefully this helps!

I'm very close to buying an iscorama (despite the outrageous cost).  My priorities are, in order:

1) single focus (either native or with an attachment)

2) capable of wide angles...  i'm thinking 50mm on full frame is wide enough for me.  With a full-frame 16x9 sensor and a final 2:40 aspect ratio, a 50mm taking lens has the equivalent FOV of a 37mm spherical lens, regardless of whether using a 1.5x or 2x anamorphic, due to cropping of the sides to get from 3.56:1 or 2.66:1 down to 2.40:1.  And a 37mm FOV on full-frame is pretty wide.  

3) 2x stretch (for the more exaggerated bokeh)

The iscorama ticks the first 2 boxes, but not the last.  I've rented one to play with an I'm pretty happy with it.  I also love how compact and simple it is.

As far as I can tell from reading these and other forums, there does not exist a lens (or setup) that ticks all 3 boxes unless you make the jump to proper (and very expensive) cinema anamorphics, most of which are also much bigger and heavier.  

A 2x lens + rectilux setup probably comes the closest, but it definitely vignettes with a 50mm taking lens, not to mention the added size and weight compared to the iscorama.  I've also read about the single-focus B&H lens that a user here modifies, but it seems to be even less friendly for wide angles.  

Before I pull the trigger on an iscorama, I just wanted to check in with this very helpful forum to make sure there's not some magic solution out there I'm missing, that would be single focus AND wide angle friendly AND 2x.

Thanks for reading!  

Thanks Hans!  Very helpful information.  By the way, would this effect also happen with the 36 (single-coated version)?   I imagine it would, but the flares would be slightly further towards the edge of the frame since the rear element is larger?.  

I will give your o-ring solution a shot!

I rented an Iscorama pre-36 to test out, and I noticed the flares were very strange.  There was a horizontal streak as expected, but the streak was surrounded by a bunch of criss-crossing lines at odd angles.  I found a video that showed the exact same thing i was seeing in my tests (starts at 2:07):  

At first I thought maybe it was an issue with the taking lens (I'm using Contax Zeiss lenses), but I tried several different lenses and they all flared with those weird surrounding lines.  I also tested my Kowa B&H with the same taking lenses and same setup, and it looked normal with just horizontal streaks.

Does anyone know what's causing these weird flares?  I'm pretty sure I've seen some flare tests with the Iscorama 36 and pre-36 that dont have this problem, so I'm a little confused what could be causing it.

If anyone has any insight please share!

Thanks guys!

So if it doesn't say "MC," it might be single coated or it might be multicoated.  That ebay listing looks nice, and definitely looks single coated.  The price seems a little crazy though, compared to other lenses I have seen being sold. 

I've searched the forum but I can't find a clear answer about this one.  

If a 36 has the "MC" written on it, obviously it's multicoated.

If it doesn't have the "MC" written on it, does that mean it's single-coated?  Or did they just make multicoated lenses without the "MC" label for a while?

Does anyone own a 36 that's definitely single-coated?

Thanks for your help!