Go Back   Steve's Digicams Forums > Digicam Help > General Discussion

Reply
 
Thread Tools Search this Thread
Old Jul 20, 2004, 5:02 PM   #1
Junior Member
 
Join Date: Jul 2004
Posts: 3
Default

Hey all

I recently purchased a 3X phoenix Teleconverter for my 10X Finepix S5000..

Im pleased with the quality of the pictures, however when I use the full optical zoom, some parts of the picture look blurry.. This goes as you reduce the zoom slightly, and the blurriness disappears altogether...

Being a cricket photographer, I really want the most zoom I can get.. I was wondering if anyone knows what causes these issues, and if there is anything I can do to alleviate them?

Many thanks
Langeveldt is offline   Reply With Quote
Sponsored Links
Old Jul 20, 2004, 5:56 PM   #2
Moderator
 
calr's Avatar
 
Join Date: Sep 2003
Location: Beaverton, OR
Posts: 8,466
Default

Any zoom lens exhibits its worst performance at the extreme ends of its zoom range. Put a telextender on it and you are magnifying the problems. The sharpest performance will be in the middle of the zoom range. This applies to all zoom lenses and cameras.
calr is offline   Reply With Quote
Old Jul 20, 2004, 6:08 PM   #3
Senior Member
 
marokero's Avatar
 
Join Date: Jun 2002
Posts: 769
Default

Too much glass in front of the sensor, some of it not perfectly mated to the camera's own lens system, that's the culprit of the blurriness you are experiencing.
marokero is offline   Reply With Quote
Old Jul 21, 2004, 2:59 AM   #4
Senior Member
 
Mikefellh's Avatar
 
Join Date: May 2004
Location: Toronto, ON, Canada
Posts: 1,707
Default

There are several good teleconverters on the market...never actually ever heard of the Phoenix one; are you sure it isn't a spotting scope or video lens (lower resolution).

Beyond the camera manufacturer's own brand of lenses, there are a few good party lenses like Raynox...here's the Raynox S5000 page:

http://www.raynox.co.jp/english/digital/s5000/index.htm

You can click on the lenses for sample pictures (with and without the added lens).

Just wondering though, if you're shooting crickets, aren't you doing closeup photography using macro, or are you trying to zoom in at a distance?

Also, are you pushing the limits of photography, the more you zoom, the more handshake is visible? The rule for handheld shutter speed is 1/focal length...so if your camera's maximum zoom (in 35mm equivalence) is 370mm, your shutter speed has to be at least 1/350th second to compensate for handshake...if you add the 3x teleconverter to it, that's 370x3 or 1110mm so you need 1/1000th of a second; of course if you have your camera on a tripod this would avoid this problem.

Of course we're just guessing here as there are no sample photos.
Mikefellh is offline   Reply With Quote
Old Jul 21, 2004, 6:10 AM   #5
Junior Member
 
Join Date: Jul 2004
Posts: 3
Default

Thanks for the feedback guys..

Pretty sure I have been scammed slightly, it was advertised as a lens for the S5000 (on ebay), but in reality I think I have been given a video lens with some adapters, that may be what is causing the problems! Is a video lens really a no no then?

So, would it be reasonable to expect far better performance from a raynox lens?

Im using a tripod on a camera with image stabilisation, so it isnt my hands causing the bluriness
Hahah!, I am not actually photographing crickets Mikefellh!!! I meant Cricket, as in a sport that is popular in South Africa, UK, Australia and India... GO to www.cricinfo.com if you are at all intrigued... It is like baseball, with the hitters in the middle of a big oval piece of grass, so a good tele lens is vital..

The attatchment is of the lens maxxed out.. As you can see, the whole thing is rather blurry, and if i was to take the same photo with less zoom, it would be sharper...

Many thanks


Attached Images
 
Langeveldt is offline   Reply With Quote
Old Jul 21, 2004, 3:34 PM   #6
Senior Member
 
Mikefellh's Avatar
 
Join Date: May 2004
Location: Toronto, ON, Canada
Posts: 1,707
Default

Video is much lower resolution than digicams, so their lenses aren't up to the task. If you look at the specs of the DCR-2020Pro:
http://www.raynox.co.jp/english/dcr/...0pro/index.htm

you'll see it's listed as "260-line/mm"...an older lens from Raynox only shows "200-line/mm". Cheaper lenses might only be 100-line/mm or less...the quality of the glass and the grinding makes a big difference.

For instance, previously I used a Canon .7x video lens but with my camera it caused barrel distortion...I saved some money in my purchase of the Canon lens but it cost me in time when I had to correct every picture taken with it. I now use a Raynox DCR-6600Pro .66x and I not only get a little more wide angle with the Raynox but I get no barrel distortion...it's worth the extra money for the better lens.

Here's my barrel distortion example...you can see how curved the window frame is, and as well see chromatic aberration (also visible in your picture):

http://img4.photobucket.com/albums/0...ide/barrel.jpg
Mikefellh is offline   Reply With Quote
Old Jul 21, 2004, 4:49 PM   #7
Senior Member
 
Join Date: Dec 2002
Posts: 5,803
Default

The way I'm going to say this is a little odd, but bare with me.

A given lens is of a given quality. Good lenses cost more money, so the lenses on the cheaper cameras are usually "good enough" for the market they are aiming for. Don't expect magic from a cheaper camera. The S5000 isn't a cheap camera, but it isn't an expensive one either.

All lenses have flaws in them, just the expensive lenses have fewer, and have special treatments applied to them to reduce problems like chromatic aboration. Some lenses are sharper than others.

This same logic applies to teleconverters.

In your case, you add the Teleconverter to the front of the lens. This means you are magnifying the light and then sending it through the lens on the camera which magnifies it again. If the teleconverter has flaws or isn't very sharp, and then that image (which is less than perfect) is magnified, those flaws/problems are magnified by the lens in your camera (making them more visible.)

This is why good teleconverters cost good money. Because you want them to be at least as good as the lens you are attaching them too.

Does that make sense?

Now, it is fairly well known around here that I have high standards in my photography. Let me just lay that out in the open to put my next comment in context.

I've seen some test pictures on the Raynox web site for their teleconverters and I don't consider them acceptable. They seem too soft. And you'd think they'd put up *good* examples on their web page (but I like their honesty of not making them look better than they are.)

But "good" is subjective. Look at their web page and see what they can produce. If you consider it "good" enough for you, then consider buying them.

Regular run of the mill converters for video are not that good. You can get away with a lesser quality picture in video because the human eye and brain compensate... its about the motion & action, not sharp picture quality.

Eric
eric s is offline   Reply With Quote
Old Jul 21, 2004, 6:39 PM   #8
Senior Member
 
Join Date: Jun 2002
Posts: 394
Default

I agree with all of the above and also would like to add that sometimes the actual attachment or threads that can be at fault. With the Panasonic FZ1 the threads were designed for filters but a lot of us imediately tried out telephoto lenses and had, at best, mixed results. Had a lot of fun doing it and now look more closely.
normc is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 3:22 AM.