norman_peters

<p>Hi all. A late post. I have a good copy of the Siggy 150-500mm. I have decided that sharpness is all about technique when using this lens. It needs a rock solid support (think a heavy tripod and good ball head), as there is significant vibration nearly always present when you press the button that inevitably affects sharpness.<br>

The best way to use it is either with a remote trigger, or using the self timer - this ensures that there is no IQ-killing vibration present (if it is on a solid mount, of course).<br>

Remember to turn off the shake reduction when it is on a tripod. I also use it on a crop body (Canon 700D) to maximise the apparent focal length, and I always use the camera's magnified LiveView facility to focus - it is too hard just via the finder to get perfect focus. I don't use a UV filter (but sometimes a polariser) and I always use the hood as flare also kills apparent sharpness.<br>

Use it racked just a bit back from 500mm to get better sharpness, and stop it down a tad - f8 seems good, but some also swear by f7.1.<br>

This all suggests to me that it is just a lens that needs deliberate use of technique to get a sharp image - I wonder if all of the complaints around the web stem from user failings in this regard, and blaming the lens....<br>

BTW mine is a very recent copy, so they may have picked up on quality control too. I hated Sigma a while ago because of old lens compatibility issues with Canon, but I have an 8-16mm Sigma hyper-wide lens and it is also a beauty, so I feel that they may be trying hard these days.</p>

<p> </p>

What about the forgotten SLR users? Here's my Tomioka Chinon 55mm f1.2:

http://farm4.static.flickr.com/3107/2557710574_b3de52740a.jpg<div></div>

On Saturday, at a country thrift store I picked up what I initially thought

was a Pentax thread lens from the 1970s. It is branded as a "Sun Telephoto

Zoom 180-410mm f5.6". The lens cost me all of ten dollars (and even then the

ladies asked me if I wanted change....) It came with its original lans cap, a

built-in lens hood, and a leather case.

I got it home, and found that it wasn't a Pentax thread, but is rather a T

mount lens. It is mechanically just about perfect, has a preset diaphram, and

has unmarked glass and is fungus and dust-free.

I have a T-mount adapter now fitted, and without taking any critical photos

yet (no time!!!) it seems to focus and zoom OK.

Can anyone tell me about this lens? Who was Sun Optics? What is its history?

How old is it?

I have Googled it to just about no avail. However, from my searching, it also

appears to be the same lens as an "Aetna Rokunar" branded optic of the same

focal lengths.

Thanks for your comments. Fisrt things first. The bride wanted an "effects" arty shot, so this had the post shot treatment she wanted.

Second, on the day of the shoot, it was 104 degrees, in tropical Queensland in mid-summer. The couple decided on a very informal dress code for the day, and it was therefore "shirts out".

As this was a spontaneous shot in between more posed ones, I had no time for better composition. I agree that the reflection would be better if more had been in the shot, but the decisive moment ruled this out.

Thanks for yor comments.

The image has not been rotated, etc, it's just a basic sample for

comment. Cheers.