Letus Extreme Resolution Chart

I expect to be a Letus EX/Zeiss owner in early '08, to go along with my HVX. I'll try to contribute to the research database here once I am : )
 
Luis Caffesse said:
Fair enough - though I don't think its truly all that obvious (to me at least) unless there is a clear idea as to what that 'sweet spot' is, which goes back to my relay lens/diffraction question above.

I guess some simple testing could determine the answer to that - seeing as the Zeiss has been tested alone and its pretty clear what the 'sweet spot' is on that lens. If I get my hands on an HVX/Letus combo again at some point soon, I'll give that a try.
Click to expand...

I think the sweet spot will always be a judgement call based on the scene conditions and the desired result. But in general, I think it wil be where there is adequate edge sharpness and appropriate DOF to create the desired look, and to work well with whatever amount of action/camera movement there is or isn't in the scene (i.e. relatively static scenes can tolerate shallower DOF etc.).

I think wide open on both camera and lens will *very* rarely be ideal, in spite of their tempting low-light friendliness.
 
I'm not suggesting that the HVX wide open would be ideal - my point is that the HVX (like all 1/3" cameras that I know of) has a diffraction limit (past which it starts to lose resolution). From testing that I and others have done it seems to be around f8.

What I'm wondering is - is there any reason why that would not be true when using the HVX lens as a relay lens with an adapter attached?

It just seems bizarre that it might perform better at f11 than f5.6
 
I figured I would continue this here as opposed to starting a new thread -

So I received a Letus Extreme a few days ago and today finally got around to doing some res chart shooting. Unfortunately, I do not have the same lens I shot the first chart with. These charts were shot with a Nikon f1.8 50mm lens (the first lens I had used was the Zeiss 50mm 1.4).

If anything - the lens I used today is inferior to the Zeiss.


Here is the chart shot at F1.8 (HVX set to 6.8)

Here is the chart shot at F2.8 (HVX set to 5.6)

And here is the chart shot without the adapter (HVX set to 3.4)

Charts were exported from DVCProHD 720P24 footage from FCP using Quicktime Conversion as uncompressed Tif files.
I opened the tifs in photoshop and saved them at 1280x720 for proper viewing.

I'll reserve my comments until anyone interested has a chance to look at them.
 
Absolutely - So it looks like the original chart was definitely the result of both a backfocus issue andd shooting at the most inferior fstop for that particular lens.

I can't wait to get that Zeiss back on this adapter to see how it performs at f2.8
 
Thanks for redoing that test, Luis. It's good to know that the things suggested were accurate.
 
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