let's compare our Zoom and Focus settings for Letus Extreme + HVX200

Well i don't take those f numbers too seriously. My measurements were made on a waveform. I'm not sure why you feel the need to so exact about this particular measurement though.
 
it had more to do with when i was comparing the light loss of the brevis vs the letus extreme on both the A1 and Panasonic cameras, to see which one could zoom in while maintaining the most open aperture possible ( most light ). Make sense?
 
I guess so, but just comparing the "fstop" reading in the viewfinder is very inaccurate. Better to compare loss on a a waveform or just on an HVX at least see how many points you lose zooming in on the IRE readout in the viewfinder.

On the HVX I found that at open f stop , to zoom in to Z72 costs about 1/2 + stop compared to a fully wide Zoom and another 1/6 stop to get to Z77 for the Letus Ex.
. At f2 its less but still similar and at F2.8 it becomes negligeable.

Hope that helps.

Lenny Levy
 
the canon XH A1, at full wide is open at F1.6

To zoom in to the GG on the Letus extreme, requires a zoom number of Z78, which closes the Iris to F2.6
 
Good news! I found my lost screw. I used a needle nose plyer to tighten it a bit more... but I cn already see how the thumbscrews will quickly strip and deteriorte that way, since they are made of plastic.

So we need from Letus better screws, made of metal please !! :) how about some wingnuts type screws?

ZOOM on my hvx. I did use it a bit less zoomed in, but last time I redid the set-up, I was very picky about my corners. I noticed that I could still see a slight "shadow" in the corners so I kept zooming in until the white frame was white all the way.

Adn that was the Z80.
 
Ryan E. Walters said:
Wow, those of you have have Z settings of around 80ish surprise me- For full frame I can zoom out to Z72 (Although I keep it at Z74 to be safe.) and For academy frame I keep it at Z78 (Which I'm liking the Academy framing more - especially if I have to use different unmatched lenses, as it tends to even out the light response.) Something else that I have noticed is that I can zoom out a little more if I have the Letus mounted snorkel up, then if it is down- I have no idea why this is....

So in short I'm using: (Snorkel up)
Full Frame:
Z74
MF50

Academy Frame:
Z78
MF50
Click to expand...

Let me once again demonstrate my rookyness by asking: "what's an Academy frame?"
 
it's the field of view that 35mm lenses are designed to give you. I.e. how much image is required to fill a 35mm frame, nothing more and nothing less, which depends on how much you zoom in to your image/GG.
 
UPDATE:

I figured out why I needed to be zoomed at Z80 to see no vignetting. Because my GG was not centered. Letus instruction sheet makes it sound real easy: they say that if you are using their braket, and some support rails, you should be lined up right for the get go. But it is far from the truth. In fact I was very far off, image was too far down and way too far right. As a result I had to zoom in a lot to be "inside" the GG.

This morning I unbolted the adapter and battled with it for a good 30 min straight. Having no one to assist me I found it challenging to have it lined up and be able to reach the 3 tiny screws myself and retighten them with one hand while holding the adapter in it's perfect position with the other, and without the adapter shifting position and losing it center spot. But once I got that part done successfully, I was able to zoom at only 70 and was "inside" the GG :thumbsup:. My focus remained at 50, but the grain seems finer now since I am not so close to it. I am curious to see if this will improve my image quality.

By the way I thought I would post a few photos of my current set-up, I just took them this morning. Since it is so hard to line up te adapter, I have decided to WELD it to my camera HAHA! really? No, not really but just about: I now have a case that allows me to keep it bolted on permanently:

DSC06809.JPG


DSC06820.JPG


DSC06819.JPG



By the way Schatler head is having no problem balancing all this.

DSC06814.JPG
 
Deuceofspades said:
UPDATE:

I figured out why I needed to be zoomed at Z80 to see no vignetting. Because my GG was not centered. Letus instruction sheet makes it sound real easy: they say that if you are using their braket, and some support rails, you should be lined up right for the get go. But it is far from the truth. In fact I was very far off, image was too far down and way too far right. As a result I had to zoom in a lot to be "inside" the GG.
Click to expand...

That sounds very frustrating indeed. I think something is not setup correctly with your adapter- as mounting it and getting it up and running was very simple / easy for me. Everything was "ready to go" straight out of the box for me. It was much more simple then the M2 that I had to get up and running. I wonder if the GG has become dislodged inside the adapter, or something like that. Hmmmmm........ :huh:
 
well, mine wasn't dead center either, which is also the reason i need to zoom in further than i may like to in some circumstances, but since, at the 35mm field of view, i get no vignetting, this is what i should be aiming for anyway. But it would be nice to have the option of zooming out for something slightly wider.

I just wish my GG wasnt off to the right the way it is. Because i would probably be able to zoom to Z 72, without vignetting if it were centered.
 
PaPa said:
well, mine wasn't dead center either, which is also the reason i need to zoom in further than i may like to in some circumstances
Click to expand...

I do not mean to imply that mine is dead center- it is not either. If mine were dead center, then I would be able to zoom out to Z68. Z72 and it is gone, and Z74 just to be safe for me. However I have noticed that the HVX itself is not centered perfectly- which has been discussed in other threads. That also caused some problems with the M2 that I had, and having to zoom in more, but again my experience with the Letus Extreme has been a very easy and pleasant one.
 
vignetting also depends on lighting (somehow)

vignetting also depends on lighting (somehow)

I think the vignetting" also depends on the lighting environment.

anyone tried their adapter in an ambient lit (ceiling lights) room at night?
you can get a very spot lit centre - not just vignetting on the left/right, but quite a balanced even drop off all around (top+bottom+side 2 side).

a lot more camera zooming is required to crop this compared to the regular vignetting seen on one side (as gg is a little off to one side, as i read - typically the left side) during daylight/bet lit environments.

anyone noticed this yet? or this just a mini observation
(mini = double meaning :))
 
Duece, I'm just setting up my LEX today and have the same problem as you. I have to zoom in to just about Z80 to get away from the GG edge and vignetting because the frame is slightly slow and significantly too far right. I don't like how this robs me of my wide angles. But taking the LEX apart sounds a little extreme :) Did you take pictures? Is it really difficult. I don't want to have to do that but I really want my frame lined up so I can be at Z70!!!
 
You guys aren't being robbed of anything, I believe. The frame that you're using should be equivalent to that of the lens being used on a Still SLR Camera. The extra space you get is probably just that: extra. Then again, I dunno much and I'm probably wrong? Just that where I'm zoomed into right now and my SLR frame matches from the same distance.

I'm hesitant about leaving my GG centered as well, because that means an uneven focal field from the HVX to GG. Or at least I suspect it means as much. I have yet to really try it out and should be doin' so to find out.

As of now, my own safe zone's more like:

ZOOM: 27.3 (82)
FOCUS: 5.38 (50)

I'll try 72 outside in a daylight to see what happens.
 
zoom 24mm (can go to 20 with the nikon 85mm 1.4 but 24mm is safe for all other lenses.
focus 5.64. I use the bebop foxi to lock it.
 
Charles Lowthian said:
I think the vignetting" also depends on the lighting environment.

anyone tried their adapter in an ambient lit (ceiling lights) room at night?
you can get a very spot lit centre - not just vignetting on the left/right, but quite a balanced even drop off all around (top+bottom+side 2 side).

a lot more camera zooming is required to crop this compared to the regular vignetting seen on one side (as gg is a little off to one side, as i read - typically the left side) during daylight/bet lit environments.
Click to expand...

Yes Ive noticed this with my Extreme. And for some reason it seems to do it more with other lenses than others. Mine is not dead center at all. A lot to the left.

Canon FD 20mm f2.8 (a lot vignetting, unusable in that recard I get the same field of view as with the 24mm)
Vivitar FD 24mm f2 (looks good)
Canon FD 35mm f2 (a lot of vignetting, not very good at all)
Canon FD 50mm f1.4 (looks good)
Canon FD 100mm f2.8 (looks good)
Canon FD 135mm f2 (lots of vignetting)

I get my EX1 next week so Im hoping Ill get better results with that then my current setup with a sony miniDV cam. Ill do some extensive tests then. I think my problem is partly that the camera is not centered and hits the GG so much to the left. Im hoping the problem will be less on the EX1.

Sami
 
Last edited:
Anything further on this topic from anyone? Deuce, I'm curious to hear how you've done with your "fixed" centered GG. My goal isn't necessarily to get mine to match 35mm perfectly. I'd love to get wider and less light loss if possible. I'd love to be at Z70 instead of Z80. Has anyone talked to Hien about it?
rock on.
 
You must log in or register to reply here.
Back
Top