Which camera is more light sensitive...???

[Alex]

<BLOCKQUOTE><font size=2 face="Verdana, Helvetica, sans-serif">quote:</font><table border="0" width="90%" bgcolor="#333333" cellspacing="1" cellpadding="0"><tr><td width="100%"><table border="0" width="100%" cellspacing="0" cellpadding="2" bgcolor="#FF9900"><tr><td width="100%" bgcolor="#DDDDDD"><font size=2 face="Verdana, Helvetica, sans-serif">Originally posted by S8 Booster:


The thing is that 150? is the default shutter angle. (Upright / default position). The 220? setting is not recommended by the manual unless you need it for low light conditions, more grain, less sharpness.

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hmmm. Not necessarily more grain and not necessarily less sharp. The 220 degree shutter might mean a higher f-stop, and in essence a "sharper" picture, depending on how much motion is in the shot...

As for more grain, I don't understand that idea.

Thanks for the chart!

[TA152]

<font color="#a62a2a" size="1">[ August 28, 2003 11:23 PM: Message edited by: S8 Booster ]</font>

[cameraguy]

<BLOCKQUOTE><font size=2 face="Verdana, Helvetica, sans-serif">quote:</font><table border="0" width="90%" bgcolor="#333333" cellspacing="1" cellpadding="0"><tr><td width="100%"><table border="0" width="100%" cellspacing="0" cellpadding="2" bgcolor="#FF9900"><tr><td width="100%" bgcolor="#DDDDDD"><font size=2 face="Verdana, Helvetica, sans-serif">Originally posted by S8 Booster:

This summer I have shot quite a bit with a 514XL and the images, though very good, are more grainy than the ones shot with the 1014 at 150? under similar conditions this year.


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The 514XL may use an inferior lens compared to the 1014XLS. That may cause some extra grain.

I shot a few rolls this summer with the 814XLS mostly using the 150? shutter but some shots I used the 220?. I do not see any grain increase only a slightly softer image from the slower shutter speed.

[TA152]

<font color="#a62a2a" size="1">[ August 28, 2003 11:22 PM: Message edited by: S8 Booster ]</font>

[Alex]

the shutter angle and subsequent shutter speed issue are very intruiguing to me. I think the 150 degree can work effectively in many applications.

The 220 degree can be a big help in lower light situations.

Good options. I will look into the 150 degree angle a bit more. I may have some shoots coming up where the 150 degree may give me more of what I want in the area of percieved sharpness.

[TA 152]

Got back my K40 low light comapre film today with Beaulieu 5008MS/Scheider F-1.4 6-70mm and Canon 1014 XL-S F-1,4 (shot in both 150? and 220?).

My ?∆∑∫?∑∆∑∑!!! ADSL have been down for days so I wait to post the results until the fast is back on track but the results were interesting.

Short summary.

1) The Scheider (and the Angenieuxs 6-90s actually) have SEVERE vignetting at low light. In the narrow "centre canal" there are slightly more light available than with the Canon. However:

2) The Canon produces approx the same stuff without ANY vignetting at all (Factory spec too) so the images comes out incredibly much better in total.

The shots were done in about F-1.4 and less, shooting plain gray, TV and room interior.

Will post the images as soon as I get the thing going and I will explain more about the details.

Until then, have a little patience.

R

[cameraguy]

Ok great, I anxiously await the results. In the meantime I'll fire up some coffee to get me through the wait [img]graemlins/coffee.gif[/img]

[Alex]

The Darker outer area of the picture you describe reminds me of a similar situation in video. The ENG style of video cameras (the one used by news crews that go on the shoulder) sometimes would produce the same type of darkness vignetting you describe when you completely opened up the iris and were zoomed in.

I think it happened primarily when the lens was zoomed in versus when the lens was in the wide position.

Did your test compare wide angle to wide angle, medium shot to medium shot, close-up to close-up between the Beaulieu and the Canon?

I hope that question doesn't sound too demanding. [img]graemlins/angel.gif[/img]

I bought an aftermarket lens for my 1/2 inch 3-chip camera, and the darkness vignetting you describe did not exist. I was told that the lens I purchased for my 1/2 chip camera was the same lens that was used on the 2/3 inch cameras, but my after-market lens was designed to fit on a 1/2 chip camera.

In theory, the diameter of the lens was much bigger when put on my 1/2 inch 3-chip camera compared to putting that same lens on a 2/3 inch 3-chip block.

Perhaps the combination of a bigger lens diameter and shorter lens Barrel length (on the Canon) reduces the darkness vignetting S-8 Booster described?

[Alex]

One other test, (for anyone who owns a Beaulieu camera) would be to see if and when the darkness vignetting goes away when one starts zooming out from the telephoto position.

Knowing the exact mm setting (for instance, perhaps at 56mm on a 70 mm lens) that the vignetting disappears, would be useful to know.

Also, at what f-stop, when one is completely zoomed in, does the vignetting go away?

This of course, is useful to know if it turns out that the vignetting is caused by an open f-stop ( F1.4) and being completely zoomed in.

[TA 152]

Info:

The "greycard" is a grey/white roof and the light is barely below F 1.4. All shots are with the 85 daylight filter removed (lamp position).

There are some slight video flicker from the transfer. I did choose the "medium" exposed frames and the scan lines are avoided to influence on the images.

Vignetting:
The Canon lens is guaranteed free of vignetting as per the original documentation in the maintenance manual. Slight non visual vignetting exists in the MACRO tele position.

For reference the "blank" image is posted last to show the "natural" vignetting produces by the projector/hotspot and possibly teh video camera used for capture.

All images are a bit soft in center, most likely because the projector might have been slightly out of focus but it has basically no influence on the light sensitivity issue.

All takes were shot at a locked wide open F1.4 and locked there.

The first shots with the Beaulieu was at approx 9fps. This was an error but I notice so I calculated by ear and found the 45 fps to offer about 18 fps (at least no higher) by comaring to teh Canon 18 fps so they turned out quite identical in speed. After speed up to 18 fps this should be no factor for incorrect results.

As it turns out teh beaulieu/Schei do offer more light/exposure/sharpness especially in the room shots. However, this is only valid in teh centre "light canal" as the lens vignets severely sn drops off a lot outside the centre.

If you examine the images from both cams you will see that somewhere outside the centre the B produces the same grain as the Canon and in the "corners" the Canon is superior by both 150 and 220? XL setting. The B corners are totally black while the C still produces some exposure.

The exposure of the Canon is constant over the image area, Since it is all equal it will naturally produce some more grain in the center than the B but the C grain is consistent producing a very even image.

To put this short:
The Schnei would never passed the QC at Canon. Nor would the Angeieux F 1.4 6-90 lens commonly used on the Bauer 715 and also available for the Beaulieus which produces vigetting similar to this Schnei.

As far as I can judge the AVR light sensitivity is not to different between the cams. The Beaulieu have no advantage over the C under these circumstances, all image evaluated.

If heavy vignetting is acceptable the Beaulieu have an advantage.

If not, the Canon has an advantage.

For "normal" use of F 1.4 and higher I personally regard the Canon way better than the Beaulieu.

Beaulieu 5008 MS/ Schnei 6-70 vs Canon 1014 XL-S

"Greycard"
[img]ftp://ftp.filmshooting.com/upload/pictures/0BEAU1R_9FPS.jpg[/img]
Beaulieu at aprox 9fps due to error in cam.
Heavy vignetting, increased grain out of the centre canal-

[img]ftp://ftp.filmshooting.com/upload/pictures/0CAN1R.jpg[/img]
Canon 150? 18 fps
More grain all over the image but very consistent.
Vignetting caused by projector/video cam.

[img]ftp://ftp.filmshooting.com/upload/pictures/0CAN1R_220.jpg[/img]
Canon 220? 18 fps
Almost the same, less grain. Look at the light in the upper right corner. The C lens is noticeably brighte rin teh corners than teh B/Schei

TV shot:

[img]ftp://ftp.filmshooting.com/upload/pictures/0BEAUTV1_XFPS.jpg[/img]
Beaulieu 9 or 18 fps
Visual vignetting.

<font color="#a62a2a" size="1">[ November 04, 2002 05:30 AM: Message edited by: S8 Booster ]</font>