Re: [APML]: 300mm F2.8 lenses..which brand?

["Philip Perkins" <philip@astrocruise.com>]

The Astro-Photography Mailing List
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Michael

> I do think that the 300 mm focal length
> has many uses.  I have taken numerous photos with it.  Some years ago Chuck
> Vaughn took a large series of published B&W photos with his 350 mm lens.
> Also Bill Fletcher and others have taken many great photos with their 300 mm
> focal length Schmidt cameras.  Likewise the 48-Schmidt cameras at Palomar
> and Siding Springs have about the same field coverage as a 300 mm lens for
> 35 mm.  

I probably did leave out some objects which are best composed at 300mm -
there are a whole raft of things up there that I have never attempted yet!
I was really trying to convey my impression that so far most of the objects
I go after are best composed at 400mm and my 400mm gets a lot more use than
my 300mm.

> Among some of the objects I have used the 300 mm focal length for
> are:  IC 1396, 
Personally I think this one works better at 400mm

> LDN 857,
Don't know this one

> combined IC 1805 & IC 1848, 
This can be done at 400mm but I agree it's better composed at 300mm

M24 with M17, combined
I think this works nicely at 400mm

> North American and Pelican nebulae and many more.
I also think this works better at 400mm

When I started out with my Tamron I assumed that 300mm would cover most
things but I quickly found that nearly all of the most popular objects are
covered better at 400mm.  Take combined M8 and M20 for instance, combined
NA and Pelican, and the Veil Nebula.  Even your famous S-147 works well at
400mm, IMO.  This may be a matter of taste - whether ones preference is for
nebulae in close up or set against a wide vista of stars.  The 400mm
certainly gives a closer crop on some of these objects, although they are
all fully covered. The nice thing about 400mm is that it is long enough to
do quite a decent job on several objects (such as the California Nebula, the
Pleiades, and even M31) where 300mm is definitely too short.  Of course
ideally I would not do M31 and the Pleiades at 400mm but currently I have
nothing in between that and 1500mm.  I am finding my 400mm very versatile
and it gets used much more often than my 300mm.

Regards
--Philip

Philip Perkins  --  philip@astrocruise.com
51 27'N 1 36'W  --  Wiltshire, UK
43 54'N 5 32'E  --  Luberon, France
Astrocruise     --  http://www.astrocruise.com