TH55 Add-On Lens???

[tonyreynolds]

Has anyone out there played around with adding an auxillary lens to the TH55 to sharpen the camera's images?

I find that the images display *okay* on the TH55, but they are unacceptably fuzzy when displayed on a computer screen or when printed.

I have read that there is a *sweet* spot for the focal distance of about 4-5 feet or 1.25 to 1.75 meters, but have been unable to get ANYTHING that is acceptable.

Please no flames, I went into the TH55 knowing that the camera was significantly less-than-stellar, but coming from the NZ90, it's a HUGE let-down.

My reasoning is that if they could add a lens to the Hubble to refocus the fuzzy images, could it be done with the TH55?

Any thoughts?

Tony :o

[Reggie]

Tony,

Check out a product from Brando:
http://shop.brando.com.hk/cameralens.php

[jj2me]

I think this is the nature of the VGA-camera beast. I had the same feeling when I used my first 640x480 digital camera, which came in a camcorder. The picture showed up so nicely on a TV, but the print was horribly fuzzy, what was I doing wrong? Then I compared the size in KB of the JPEG file, with the size of a similar scanned 4x6 photo, and found they were the same size when I set the scanner to 150 dpi, I think it was.

Just like in any photography, *adding* an additional lens won't improve the clarity, otherwise, you would see extenders used for telephoto, rather than having to switch entire lenses for best clarity. (All the Brando lenses have other purposes, like macro, tele, filter.)

[daver]

jj2me is right. it's the nature of the VGA camera. i've a Sony digi-cam at home (really old one from Air Miles) that's only 2.0 MP, and i changed the settings to take 640-480 pictures and compared file size and quality. the digi-cam does a nicer job simply because it's designed to take pictures and only pictures. the TH55 isn't an actual camera. the camera is just there really for multimedia purposes - i.e. Sony put it there for fun.

[Tam Hanna]

Try cleaning your cam's lens from dust, etc. I had a similar problem with a friend's SX1-after having the lens cleaned, ther images got better considerably.

[tonyreynolds]

The problem is NOT the VGA file size, ie, 640x480; I can take excellent images with any of my other cameras at that size, even the NZ90.

The problem is the LENS, and as noted above, the lens is only good enough to take an image for SCREEN DISPLAY, not for PRINTING,, and even on the screen, the image is fuzzy.

I did an experiment shooting through my eyeglasses and there is a definite improvement in sharpness over the raw TH55 image; not stellar, but better.

One additional problem is that the TH55 camera, and indeed ALL of the cheap cell phone/PDA cameras is the CMOS imaging chip, which in MOST cases will not provide the same quality image as a CCD imaging chip. I say *MOST*, because Canon's Digital Rebel, for instance, is a CMOS camera, albeit a 6MP camera.

I'll keep playing with lenses I have laying around and report back here if I come up with a significant improvement...

:rolleyes:

[tonyreynolds]

Tony,

Check out a product from Brando:
http://shop.brando.com.hk/cameralens.php

Reggie:

Thanks, I looked at those, but they're telephoto and wide angle only. Might be worth playing with though. The next time I order a screen saver from Brando, I'll throw in some lenses...

Tony

[tonyreynolds]

New Nokia boasts Carl Zeiss lens
Click for: New Nokia boasts Carl Zeiss lensThe mobile phone industry is trying its best to rival low end digital cameras and the latest Nokia might just do the trick. The Nokia N90 multimedia boasts a Carl Zeiss lens, 2 megapixel resolution, 20x digital zoom (ahem!), auto focus, flash, macro mode and VHS video capture. The flip and twist N90, reminiscent of the Panasonic AV series, houses a RS-MMC card and its PictBridge-compatible, and Bluetooth-enabled for wireless printing. The interface looks quite advanced for a mobile phone and the N90 also provides on-phone editing capabilities. The N90 multimedia is expected to become available in the second quarter of this year. (13:35 GMT)

http://www.dpreview.com/news/0504/nokia_n90.jpg

(from dpreview.com)

[tonyreynolds]

Try cleaning your cam's lens from dust, etc. I had a similar problem with a friend's SX1-after having the lens cleaned, ther images got better considerably.

This is not a matter of a dirty lens. The lens is clean. The problem is an out-of-focus image being delivered to the imaging plane by the lens, ie, myopia.

The lens point of focus is slightly in front of the CMOS imager, giving an image similar to what a near-sighted person would see without corrective lenses.

Tony

[Ion Control]

Just like in any photography, *adding* an additional lens won't improve the clarity...

Not true. Adding another lens can most certainly enhance clarity, the Hubble telescope serving as a perfect example (as the OP said). As we know, a picture is the result of a cone of light being focused through an aperature of fixed or variable size. At the point where the various rays come to a point, you have "perfect" focus. On the typical "fixed focus" camera, this point is not variable, so if the film or CCD plane is often even slightly, you will experience less-than-ideal quality. Luckily, the farther away an object is, the easier is to focus. Focusing up close is where it's difficult. An AF or MF camera takes this into account and allows you to increase/decrease the distance of the lens from the focal plane in order to optimize focus. Since the TH-55 appears to be optimized for close shots, you will necessarily lose some detail as objects further away are out of focus. If one knew enough about the various lens parameters, an additional lens could be manufactured to alter the light path and effectively compensate for the relatively strict focusing of the 55. This is similar to what was done on Hubble. The initial mirror was ground incorrectly, so a new lens was installed to alter the light to specifically compensate for the imperfection. The 55, though not "flawed", could be similarly corrected with the right lens. And if you don't believe this, simply look at before and after shots of the Hubble...

Re: the 640x320 debate, that is important. There are only so many pixels to go around. An image of a house 1,000 yeards might only have 1,000 pixels to compose the house while at 100 inches, all 200,000 pixels are devoted to the house. This, however, is referred to as "resolution", not "clarity". Resolution is less dependent on things like the lens than the chip or film grain. Clarity more often refers to focus or overall image quality and is impacted by hundreds of external factors and can most certainly be enhanced by an additional lens.

And tele-extenders ARE often used for high-mag photography. The reason they may not be ideal is that you are unable to increase the number of photons striking the recording medium. A tele-extender magnifies a certain area of the image, but requires a brighter subject (or wider aperture/slower shutter) to work as effectively as a dedicated zoom. I have used them in astrophotography to great effect, but exposure times shot up drastically (requiring me to stack numerous short-exposure images to cut down on noise). Not many things cooler than having a 1,500mm telephoto lens at f12 :)

But, when it all comes down to it, I think the main problem with the 55 is simply the lens *size*. That is a VERY small lens. And, as any astronomer will tell you, aperture is king. Having such a small apeture on the 55 almost guarantees poor images. if the lens actually filled the little recessed area, you'd have better results (vignetting aside).

[tonyreynolds]

Thanks, IonControl!

Tony :)

[jj2me]

The problem is NOT the VGA file size, ie, 640x480; I can take excellent images with any of my other cameras at that size, even the NZ90.

The problem is the LENS, and as noted above, the lens is only good enough to take an image for SCREEN DISPLAY, not for PRINTING,, and even on the screen, the image is fuzzy.

I did an experiment shooting through my eyeglasses and there is a definite improvement in sharpness over the raw TH55 image; not stellar, but better.


:rolleyes:

Sorry, I read your description of "fuzzy" and first thought of my experiences, which were more like "grainy," as opposed to out-of-focus, which "fuzzy" implies. Tried 2 TH55s today and they both seem "OK." Seem to be in best focus when closer, like 3 feet, which is closer than I expected for a fixed focus camera. But neither very good, e.g., can't capture a typewritten page (held at a distance from the camera so that the full length of the page is just captured) well enough to read or run through an OCR program. Then tried with eyeglasses, and got 3 lines of text right in the middle that were noticeably clear, but couldn't draw any conclusions from that (the eyeglasses have some astigmatism fixes ground in). So not sure, maybe my 2 have the same problem? Sorry I couldn't help.

[tonyreynolds]

I took several test pictures of a newspaper laying on a desk yesterday evening as a test... I was able to read all of the headlines and titles and some of the copy. I'm going to keep experimenting. Heck, why not? It's fun!

Tony :D