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September 22nd, 2003, 02:42 PM | #16 |
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But I've looked down into the lens of the TRV950, turned the aperture control wheel and seen those two diaphragm blades go from fully open to fully closed. I simply can't believe that Sony would abandon such a well tried and tested method of controlling the exposure and go for a light dump. But I'm happy to be proved wrong.
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September 22nd, 2003, 06:07 PM | #17 |
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I have Completed futher testing. Here are the results this time.
Tom I played the tape in another camera. It registers the same readings as recorded by the 950. I also did a test on carpet. The readings are. The 950-- is Auto, 1/60, AWB, F1.6, 18db. The D8-- Auto, 1/60, AWB, F1.4, 9db. TRV950--------------------------TRV510--D8 Concrete---------------------------Concrete Sun------Shade---------------------Sun-------Shade Auto------Auto---------------------Auto--------Auto 1/60------1/60---------------------1/60--------1/60 F.4-------F.4-----------------------F22---------F6.8 0db-------0db-----------------------0db----------0db AWB------AWB----------------------AWB---------AWB My Hand---------------------------My Hand Sun-------Shade-------------------Sun-----Shade Auto------Auto----------------------Auto----Auto 1/60-------1/60---------------------1/60----1/60 F5.6-------F4------------------------F22------F4 AWB-------AWB----------------------AWB-----AWB It appears that the readings that are at F4 --F1.6 are recorded correctly, Any thing above F.4 are not. once in awhile I will see a 5.6(as my hand) . I have never seen an F8 or above. As I stated before, Sony seemed to not be able to understand my question. I even sent them a demo tape. There was no comment.
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September 23rd, 2003, 12:18 AM | #18 |
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Again, I hate to bore those who are just passing by, but the readings your D8 cam gives are much more true in the photographic sense. Your D8 shows a three and a half stop difference between concrete in sun and shade - exactly as I would expect it to. The 950 shows no exposure difference, so (unless the exposure on the tape varies wildly - which you don't mention so I guess it doesn't) then
a) either the Info readings are wrong and the lens *is* stopping down b) an ND8 automatically jumps into place when you go into sunlight. c) An electronic light dump takes place. The readings from your hand are even wilder. D8 shows a 5 stop difference and DV shows 1 stop. Let's back-track. Say you wanted to use the TRV950 at small apertures for large depth of field at telephoto. It looks as if your cam won't 'allow it'. What sort of photographic tool is that? Here's another test for you to try. Turn the 950 on and switch to auto exp. Zoom the 950 to telephoto an look down that lens. Have a 'pencil torch' (Maglight) by your ear and shine it on axis down the lens barrel. You should be able to see the diaphragm blades react to the light exactly as they would to sunlight. Do they stop well down as they do in manual? tom. |
September 23rd, 2003, 02:24 AM | #19 |
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Tom, seeing the diafragm moving doesn't exclude the other possibilities..."What kind of photographic tool is that?"...Remember that high end dig photo cams also limit their F settings (mainly for avoiding diffraction) See e.g. http://www.dpreview.com/reviews/nikoncp5400/ . It still looks strange that Sony doesn't mention anything about this behaviour.
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September 24th, 2003, 02:42 PM | #20 |
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I believe there is no iris in the TRV 950, and no ND filters as well. Has anyone looked inside the camera? Is the exposure delt with just electronically "post-CCD"?
I still haven't got ND filters, but I'm sure they will give me better pictures in sunlight. In bright sunlight the picture seems to be a bit "washed out." |
September 24th, 2003, 04:36 PM | #21 |
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I did shine a light into the lens and the iris does respond to the light. The iris is 2 blades,they form a diamond shape which gets smaller as light enters. The results recorded on tape are good. Very close to my other cameras. So I assume it is just something in the recording of the information in the data code section.
Thanks to all of you, who responded to my questions, I was reading on another site about shutter related problems they were experienceing with other models of Sony camcorders. So I guess in this age of high technology, it is difficult for even the designers to solve or know all the little quirks. Thanks again, I really enjoy having access to this site, It is not like some others, no nonsence, but very informative and to the point.
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September 30th, 2003, 12:38 PM | #22 |
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It seems not so many people are interested in this topic, however I am quite concerned with this issue since the model is supposed to go upto F8, why it does not?
What if you use manual focus? does it ever goes up to F8???? |
September 30th, 2003, 01:10 PM | #23 |
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The 950/X10 most certainly does have an iris diaphragm Frode, and it's as Bob describes - a two bladed afair forming a diamond at large apertures and a circle at very small ones. Two blades are always less efficient than 6 bladed ones (as used in the TRV900 and VX2k) but they're cjheaper and generally have less inertia and momentum, so can be made to vary the aperture very quickly indeed.
So the lens does indeed vary from f1.6 to f8 in both the manual and automatic mode, though the readout from tape appears to be incorrect at times. I suspect that the aperture is not shown while shooting simply because the F stop and the T stop vary considerably due to in-built and automatic ND filtration. I'll know more later this month when Sony send me a PDX-10 for testing, and I'll report back here. tom. |
September 30th, 2003, 10:48 PM | #24 |
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In response to your question about trying to select an F8 in manual mode. I haven't been able to select any F stop. It is my understanding the TRV950 is shutter priority only. It appears to me that, wnen you try to make a change of stops, the only thing that happens is the iris just closes or opens while the selected F stop remains the same. The only thing that happens is the picture is either over or under exposed. I have never seen an exposure F8. Only one time, I was able to get a 5.6 reading was a close up of my hand in full sun. As I stated before the exposure always is good. Also the depth of field seems ok. As I stated before I also have a Sony Digital 8 Camera. It will register every F stop from 1.4 to F22
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October 1st, 2003, 12:49 AM | #25 |
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Hi Bob - I really will be surprised to find that the 950/X10 is shutter priority only. Because of the tiny chips Sony have apparently held the smallest aperture to f8 to limit the destructive diffraction losses and this will mean upping the shutter speed when f8 is reached and the light gets brighter. Is there no menu selection offering "Auto Shutter - on/off"?
The VX2k has f11 as it's smallest selectable stop but the camera will happily shoot at much smaller apertures than this if you don't switch in the ND filters. On replay it'll always say you shot at f11 even if it was using f16, f22 or f32. Bob, you say: 'wnen you try to make a change of stops, the only thing that happens is the iris just closes or opens while the selected F stop remains the same.' This doesn't make sense as an opening or closing aperture *is* varying the f stop. The readout may well be wrong (always insisting that you were using f4 or 5.6), but this doesn't alter the fact that the aperture blades are constantly on the move. But if as you say the exposures are good then all is working well. I just suspect the info readout - that's all. tom. |
October 1st, 2003, 01:19 AM | #26 |
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Tom, this was discussed in some threads months ago, Auto-Shutter option in most Sony camcorders don't work (might be a bug in the firmware)
I tried, on 950, it doesn't show any difference be it on or off. |
October 1st, 2003, 05:07 AM | #27 |
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Yik, "Auto Shtr" which can be selected "on" or "off" in the menu in many Sony cams works perfect if is being used for the right purpose. First of all it's only meant for "full auto" applications (no prompts !), so not in AE modes or other semi-auto modes where shutter or aperture are being presetted. Of course also full manual is excluded.
It basically allows to make a choice between a locked shutter speed (auto shtr "off"), or a variable one (auto shtr "on") when shooting in "auto" Selecting the first option the shutter speed is locked at 1/60(1/50) and the aperture closes down at high brightness scenes sometimes far beyond F11, resulting in sharpness reduction due to diffraction effects The second option will limit the aperture closedown but goes into a higher shutter speed which could result in (background) strobing with high brightness scenes. So, only in "auto" shooting (nothing prompted !) the shutter speed can be set locked or unlocked in the menu by choosing resp. auto shtr "off" or "on" . |
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