Must Decide Today: Sony 1.7X Telephoto
 

Took a brief look at a Sony VCL-HG1758 telephoto with 58mm threads. Seemed (but not sure) that the lens introduced some loss of sharpness and loss of contrast. Anyone have experience with this lens? Have you noticed these problems, or should I relax?

I'd send it back. You don't have that warm fuzzy feeling that you've done the right thing. It'll eat at you and you'll always wonder.

Here are some shots I took with that Sony 1.7X tele lens......with a GL2 and HG lens. I found it quite good and the dv video footage is excellent.

http://stevenunez.com//GL2frames/gl2grabs.html

Good news! I didn't know if I was going to get a chance to take a second look at the lens before having to make a decision. It cut into my beauty rest but I was able to take a closer look.
Here's what I did. I used my new "super mombo" tripod for the first time. I put my VX on there and shot three different scenes in manual exposure with the memory stick set to highest resolution. I shot the scenes first with the Sony 1.7X. Then I removed the tele, moved the tripod closer to get the same framing, and captured the scene to memory stick with the VX lens.
The three scenes were: straw end of a broom, close-up of a business flyer, and a wall of hanging portraits.
I imported the stills to computer and viewed them full screen
on a 21" CRT Trinitron monitor. I looked closely at the straw strands of the broom and the printing on the business flyer to look for loss of focus. I saw *no* difference in sharpness between telephoto on the cam or off.
I then imported the stills into my NLE and viewed them with a video scope called a Histogram. This scope will give the average luminance (brightness) of an image. It can also tell the contrast of the image by telling you the numerical values of the whitest
white and the blackest black. From looking at the results, I can say that the Sony tele does *not* cut down on the amount of light entering the camera. I can also tell there was a *very slight*
loss of contrast when the lens was on. This was to such a small degree as to most likely be unnoticable. I would imagine, if you felt you were able to notice this, a slight tweek in post would be all that would be needed.
Finally, I looked for any color shifting by looking at the stills under a Vectorscope. This scope shows the strength and direction of coloring in an image. From this I could tell there was
a slight increase in color saturation across the board, not in any one direction. Just looking at the images with my eyes, they seemed slightly warmer. If these changes were a concern I would say, again, they're easily tweeked in post. Actually, I preferred the warmer look of the shots done with telephoto on.
All in all, I'm very pleased with the way things turned out. And with this lens in general. It's bigger than I thought it would be--about 4" across the front glass; the glass is recessed into the lens to afford protection from side-light flares. A nice touch is the 3/4" grippy rubber strip encircling the end of the lens. This aides in attaching and removing the lens. There are no front filter threads--myself I don't use "protective" filters anyways so it's not an issue.
I paid $270 for it. The next step up is the $400 Century 2X.
The Sony seems good enough that there seems little reason for me to spend more.
One thing I should mention regarding the Sony lens: it begins to vignette at about half way between the wide and tele zoom position and gets progressively worse as you go wider. Don't know if this is the same with all the telephotos on the VX/PD.
Anyone here using a different brand tele who'd like to share how it is regarding this vignetting issue? I do own a consumer 1CCD cam that also has a 1.7X tele and it does not exhibit this vignetting.