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Old Aug 26, 2008, 5:11 PM   #51
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Adventsam wrote:
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Oh, then you are not a photographer in which case polarisers/nd's etc will all be lost on you too!

Also, the adapter will allow you to add a wide-angle/tele with ease but then you wont benefit from that or a close-up achromatic lense/filter.
I believe I've probably been a photographer longer than most. My answer was very specific to UV filters which may have had a slight benefit in the days of film with their extended UV sensitivity but are useless in digital photography. I did not address the sliding adapter at all nor anything else you've brought up. Circular polarizing filters have a benefit at times but no one is going leave that on at all times because of the 2-4 stops loss in light. If they can get away with that loss at all times they are not being very adventurous. The samples I've seen on the web by someone touting achromatic close-up lenses suggested to me that the person could have made identical photos without the lens if they'd just learned to use their camera before they added their "must have" attachments.

The sliding adapter is an interesting concept. I question, knowing the the weight of high quality auxiliary telephoto and W/A lenses, if the zoom motors in P&S lenses can handle the extra load imposed by that type of adapter.

Photography is first and foremost about seeing, not the number toys in the camera bag. As one well published photographer of the '50s told a photography magazine, when they asked for technical details for a photo the magazine was about to publish, "A camera was faithfully used." Two weeks ago I would have liked to have had a wider angle lens than I had when photographing the interior of an 1850 era working class house but I took interesting photos anyway because I adjusted my "seeing", an intellectual function not an optical function, to find interesting elements within the functionality of the camera I had in my hands. Next weekend I will probably have to again"see" when Itake interior shots of an LST.

I bought the camera knowing full well it's limitations, including attachment because it had the telephoto and macro capabilities I wanted.I won't waste my time crying over what it won't do as that interferes with doing what it can do - taking the photos I want.
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Old Aug 28, 2008, 5:21 AM   #52
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I respect your comments!

Maybe I'll re-evaluate my use of the uv, it's left permanently on the camera, I would like a wider-angle though! and polarisers and nd's are useful too so should be readily attachable, but as you say, "A bad workman blames his tools!"
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Old Aug 28, 2008, 6:04 AM   #53
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Adventsam wrote:
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....Maybe I'll re-evaluate my use of the uv, it's left permanently on the camera...
In my 35mm SLR days, with a 35-80mm f/2.8 lens mounted by default, and often an 80-210mm, there was a big, wide,chunk of expensive glass on the front of the camera. When out & about, especially in the wilds, it was difficult to keep clean & safe. I routinely had a UV/Haze filter fitted a lot of the time, purely for lens protection, paying theprice of an extra, optically unncessarylens element.

I also had an irreplaceable pocket Rollei 35. That had a filter mounted as well, on the end of its retractable lens barrel, because it lived in grubby places, such as breast pockets. Sadly it drowned, as the only casualtyin a boating accident.

Now, with a tiny Casio pocket camera whose lens retracts behind shutters, and a Kodak Z712 with a retracting lens about 30mm wide at the front and a quickly & easily applicable cap, I don't so much feel I need it.Anyway the retraction precludes it. That said, I don't dare clean the front element as often as I did then. The whole camera now is cheaper, relatively, than the interchangeable lenses were individually.

As for the optical properties, both B&W and colour film were in fact over-sensitive to UV, so an argument could be made for a special filter. I don't know about current digicam sensors. However, many glasses are good UV absorbers.

A photochemist colleague of mine, working much of the time with UV lamps, only wore specialist goggles when he really needed them. He knew he was safe around his lab, because he'd measured the absorbance spectrum of his everyday spectacles (eyeglasses). Visitors were always issued with goggles.
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Old Aug 29, 2008, 11:34 AM   #54
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Look at this info re hot-mirror, as you know I'm getting either a 12/15, have postponed order for 12 until I have sneak at the 15. Anyway my joy is having both stills and hd in a single cam, I have numerous"hybrids" and all ccd's are plagued by purple smearing, over sensitivity to certain lights, read below and see attached. I have seen the ccd smear in z12 videos so know it is a problem but the saving grace of the 12 is the is lense. Unbeleivable as it may sound the 12 is the only reasonable superzoom with usable hd video that is is stabilised. It aint perfect, it focus hunts etc but the video is stable and 720p is good enough for me especially as its mp4 even better. Anyway the one thing that really annoys me is purple smearing, after looking around and trying numerous things to eliminate it, polarisers/nd's etc etc I stumble across this, a hot mirror filter , read on and see results here;

http://www.pbase.com/nh/hotmirror

A hot mirror filter cuts IR light. According to Kodak's site it greatly reduces near-infrared light, resulting in less noisy and more color-accurate images. Basically it blocks light in the 700nm to 920nm wave length. This light passes through the Bayer filter and exposes your sensor.

The Bayer layer is needed because All image sensors are grayscale devices that record the intensity of light from full black to white. To add color to a digital camera image, a layer of color filters is bonded to the silicon using a photolithography process to apply color dyes. Typically, an RGB camera would have three image sensors with color filters, as well as an optical prism and a special optic capable of sending the incoming light to the three different color sensors. Each image sensor will then create 'red' 'green' or 'blue' digital samples. However, to lower the cost of an RGB camera, a new approach was developed to simplify the camera's optics such that only one image sensor is needed instead of three. This approach uses color filter arrays (CFAs) in order to capture RGB images.

A Bayer filter uses a checkerboard pattern with alternating rows of filters. The Bayer pattern has twice as many green pixels as red or blue and takes advantage of the human eye's tendency to see green luminance as the strongest influence in defining image quality.

What the Hot Mirror filter does is prevent the IR (or near IR 700nm and up) from reaching the CCD. It seems that the Bayer layer allows IR to pass through the red and blue layers (thats why it looks purple).

As for the Neutral Density (I assume you are asking if it effects your exposure), the answer is - yes, you loose 20% of a stop (give or take) or roughly 2/3rds of 1/3 of a stop. I'm not sure that you even lose that in the visible portion of the light. (If the IR is adding to the amount of light exposing your ccd and you cut it out - I guess the image looks less bright, but more testing is needed as to if that loss is of any benefit.)

The D1H seems to have less of a problem in this area (although the D100 seems to be effected more then the D1H and less then the D2H). All cameras made today should have a hot mirror (or other IR blocking) filter installed between the lens and sensor (CCD, CMOS, LBCAST).

As for leaving it on the lens all of the time - I do. Any filter(or any glass in front of your lens) can reduce your quality and sharpness. They are prone to flare (more places for the light to bounce around in). The advantage I seem to experience with the hot mirror is the images seem sharper. I'll believe that this is because IR light focuses at a different point then visible light, so most of the IR is out of focus light anyway.

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Old Aug 29, 2008, 10:45 PM   #55
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I've got a hot mirror filter I bought some years back to try and reduce purple fringing.

It was a waste of money and it didn't help at all on the camera I tried it with (an Epson 3000z, which was likely using a Sony 3MP CCD). I couldn't detect any difference in the images, taking lots of test shots with and without it of the same subjects in the same conditions. With older sensors, I have heard that it might help (but, I haven't seen any controlled conditions tests showing that). I have seen reports that it's useful on some cameras to prevent color shifts.



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Old Aug 30, 2008, 12:16 PM   #56
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Could you try it in video mode with the hot-mirror filter in front, point it at a light with and without it and see if the purple streaks are removed?
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Old Aug 30, 2008, 3:36 PM   #57
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I don't have that camera anymore. That was around 8 years ago (I got it when it was first released in 2000). lol

Actually, I don't think I've got a camera handy with a video mode that works (I don't use videos and my dSLR models don't have one).

I've got a little pocketable Konica KD-510z that I think can take short videos at low resolution. But, I've never used that mode, and the battery isn't charged right now. I'd have to locate the hot mirror filter, too (although I remember seeing it not long ago, so it's somewhere in my office).

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Old Aug 30, 2008, 5:00 PM   #58
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Thanks Jim,

I'm convinced after a lot of research that IR is a problem for alot of cameras, may ir filters should be fitted as std, which leeds me back to my original issue, filters should be readily attachable to all cameras
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Old Aug 30, 2008, 8:07 PM   #59
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This was a popular topic around photography forums at the time I purchased the Hot Mirror Filter about 8 years ago, since everyone was trying to figure out what was causing purple fringing (since it appeared to be different compared to typical Chromatic Aberrations).

So, to satisfy my own curiosity (while hoping to get rid of the purple fringing), I bought a Hot Mirror filter and took test photos of the same subjects in the same conditions with and without it. There was no difference (identical purple fringing, with and without the Hot Mirror Filter).

I've never seen one shred of evidence that it actually helps it on any modern camera model with an IR cut filter built in (and virtually any modern CCD used in a camera is going to have one now). That's why it's so hard to take IR photos with modern cameras (they're not very sensitive to it, so you need longer exposures than desired).

If you want a camera model that's sensitive to IR, you have to go out of your way to find one. Some of the older models were more sensitive. For example, models using the Sony 2MP 1/1.8" CCDs didn't have a strong IR cut filter like the newer Sony 1/1.8" 3MP CCDs. The Sony 5MP 2/3" CCD used in the Minolta DiMAGE 7 was also more sensitive to IR. But, that stopped with later models (Sony added an IR cut filter to most later CCDs).

If you look around, you can find lots of articles on how to remove them, too (users interested in IR photography do that). See this Google search for examples:

http://www.google.com/search?hl=en&q...mp;btnG=Search

There are even companies that specialize in removing the IR cut filters now. lol I think that the IR Cut part is probably bonded to the AA (anti-aliasing) filter in many designs, so you'd probably be removing both.

Because IR can cause unwanted color shifts and casts is the reason they use them with the CCDs in modern digital cameras now (with very few exceptions). So, by using a hot mirror filter, you're adding another ir cut filter (when there is already one built in), risking more problems with the extra glass (for example, light reflections between the filter and lens contributing to flare in harsher lighting).

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Old Sep 11, 2008, 9:33 AM   #60
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Hello there,

First post here (eek); have enjoyed Steve's excellent reviews for some time, but this is the first occasion I've come to post a question!

I'm thinking of getting myself a Z1012, and everything looks brilliant apart from one thing - the shutter speed. I'm currently using a Kodak that's several years old, and completely outdated. But the shutter speed can go all the way up to about 6 (maybe even 10? it's been a while since I checked) seconds.

The Z1012 however apparently only goes as "slow" as 1/30th of a second. As some one who likes to experiment (read: has no idea what he's doing) with long exposure shots, just for kicks, this is a little disappointing.

I was hoping some one might show me a glimmer of hope; is there any feature about the camera that offers a long exposure time? A shot setting perhaps? 1/30 seems far too short for me, which is a real shame.

Pete.
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