1.4m (4.6 feet) is the marking at the end of the scale.

Apart from the softness at the long end, which as Peter says, is forgivable, the thing that put me off about it was difficulty getting it to focus. Admittedly I only had it for a short time, but several times it hunted like crazy, even in good light with contrasty subjects.

I compared it at the time with my FA 28-200, which was much better. The 55-300 has similarly given me no problems.

Well I've probably oversharpened both of them a bit - I didn't spend much time on them. But I think the rim is real - it's on yours too, but less obvious. The light is from that side, and as the surface curves away, you'd expect it to be brighter. But it's a bit oversharpened, I think.

The bright spots are mostly present in the first, just not as bright. So I think they're just craters. Probably a bit oversharpened, again.

Ideal, then, from the point of view of minimising haze.

Well your mission, then, if you care to accept it...

My efforts with the original RAW files from Mannesty's pictures:

Without the TC:

[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/Mannesty_IGP4915.jpg[/IMG]

With the TC:

[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/Mannesty_IGP4917.jpg[/IMG]

In each case, duplicated the layer, high pass filter, overlay; merge layers, then USM at 75/1/1. The one with the TC was reduced to (almost) the same size as the one without, first.

I think your second one in fact has the edge on mine

This is why I'm not convinced. As you can see, the difference is very marginal in reality.

It's the same shot, just not reduced in size and further sharpened as the earlier, smaller one was.

I think a lot of this is in the PP - apparent sharpness isn't the same as actual detail resolved, and a bit less exposure makes it look better too, I think.

I would quite like to play with the DNGs if I may - I'm not convinced mine is better than the bigger one, especially since the lighting isn't the same. I'll PM you an email address..

But not of imprecision

Thanks for doing this - very interesting.

I took the liberty of nicking the larger one, and reducing it to the same size as the smaller one for comparison - it did look like there was more actual detail (as opposed to apparent sharpness).

I guess the moral is, not surprisingly, good lenses are worth having.

If you have the time and/or the inclination, it would be good if you could take 100% crops from each, reduce the one with the TC so that the moons are the same size, apply the same final sharpening (or none) to each, and post them both for comparison. I suspect the one with the TC will still be better, but the difference may be more obvious than with the JPEGs I started with.

My best long lens is a SMC-A 400mm F5.6 - I'll have to have another go with it and see if I can improve on this, which is probably my best effort to date. But attached to an old Takumar A 2xTC, the result is definitely worse.

Erm, why not?