Pentax XW 3.5mm, how tall?

[scarp15]

Compared to an XW 5mm.

I have used the Pentax 5mm for a number of years, which receives use with each of my three scopes, most notably my TV-85. Concerning the TV-85, I alternate using this e.p and a TV DeLite 7mm and 4mm such as for Lunar observing. I have considered including a Pentax 3.5mm for sometime, particularly as it is parfocal to the 5mm. I am aware that the height of these in a short refractor, can deter some, who would prefer a short more compact alternative or zoom eyepiece. I like incremental focal lengths at high power and have had no issue using the DeLite's interacting between the lofty Pentax. Putting aside a notion that the TV-85 might start to resemble a set square, the mount is a Vixen Porta 2, no issue in tensioning, therefore harking back to the question, it would be interesting to learn proportionally how much loftier this ep is.

Thanks

[Louis D]

According to Ricoh, Pentax's parent company:

Model:	XW20	XW14	XW10	XW7	XW5	XW3.5
Focal Length:	20mm	14mm	10mm	7mm	5mm	3.5mm
Lens Construction [Elements/Groups]:	6/4	7/6	7/6	8/6	8/5	8/5
Apparent Angle of View:	70°	70°	70°	70°	70°	70°
Eye Relief:	20mm	20mm	20mm	20mm	20mm	20mm
Sleeve Size:	31.7mm	31.7mm	31.7mm	31.7mm	31.7mm	31.7mm
Length & Diameter [mm]:	86 x 61	97 x 61	110 x 61	120 x 61	127 x 61	137 x 61
Weight [g]:	355g	365g	390g	390g	395g	405g

So, it's 10g heavier and 10mm taller.

And here's a Ricoh/Pentax corporate group shot:

Here's a group shot of my 3.5mm Pentax XW with the 5.2mm Pentax XL which is about the same height as the 5mm Pentax XW.

 

[John]

The 3.5mm is around 10mm taller than the 5mm. The eyecup sections are fully extended here:

[heliumstar]

It's a BEHEMOTH I have 5mm and 7mm and those are huge. I didn't expect them to be soo big when I bought them. Still, the image and comfort they provide at night are superb. Don't like them much for white light but I need to try more.

All in all. I don't see how 10g would be an issue. If you can live with 5mm I am sure 3.5mm will be fine.

[Timebandit]

 

 

 

The Pentax 3.5 XW is rather tall. The gents above have already got their data sheets and tape measures out, so beat me to those stats👍

If you like the 5mm XW  , then you will also like the 3.5mm(despite its generous size). IMO the 3.5XW and 5XW are two top tier eyepiece. Go for it, these eyepiece are real "Keepers"

 

 

[scarp15]

Thanks everyone, very useful info, visuals and feedback. The weight is not a factor and 10mm in height gain is quite negligible really, when as stated no concerns and comfortable in use with the 5mm, cheers. 

[John]

Useful for rubbish "Blues Brother" impersonations too