Takahashi FC-76DCU travel scope project.

[Icesheet]

4 hours ago, Stu said:

I have travelled with both, and there are pros and cons to each. The FC100DC will go in carry on baggage but this requires removal of the dew shield and focuser. This is fairly straightforward to do and I normally then put the dew shield over the OTA with some protection between them to avoid scratching.

I normally split the 76 in two which in itself takes up two parts of my travel case so the main benefit becomes the weight. You can also just remove the dew shield and put it over the OTA so it fits into the central section so that is more compact than the 100DC. Obviously it is thinner too so more can be packed around it.
 

For info, weights and lengths are as below including MoreBlue rings and dovetail:

FC-100DC   3.5kg   62.5cm

FC-76DCU  2.1kg    53.5cm

FS-60Q       1.95kg  42.5cm

The 100DC needs the focuser and dew shield to be removed in order to fit in my Airport accelerator case, the 76DCU just needs the dew shield to be removed and of course the 60Q fits in fully assembled.

The 2” FTs work very well with, and suit all these scopes in my opinion. I find the 2025 is better with its longer travel range.

In terms of performance, they follow theory in my view ie you can see the differences between 60, 76 and 100. I think the 100 definitely shows more detail on planets and the Moon, and splits tighter doubles. The 76DCU or Q are fantastic for their aperture, but I don’t think the Q addition enable it to beat the 100.

 

3 hours ago, DirkSteele said:

Agreed. Even a “perfect” 3” scope which one might argue the 76Q comes close to achieving will not outperform a 100mm scope that has been executed to the usual Takahashi quality, I.e excellent. That 24mm increase at this aperture makes a heck of a difference.

Thanks. Makes sense that the 100 bests the 76, even with the Q module. Wasn’t sure how much of difference but it seems you both agree it would be worthwhile. I picked up the 2015BCR second hand, so hopefully just a case of an extension tube if reaching focus is an issue. 

Edited February 28 by Icesheet

[Stu]

Some more pics of the scopes packed down to show the comparison. When split, the 76 does feel quite a lot smaller and would go into a short case.

 

[Icesheet]

Thanks for going to that trouble. Very illustrative and helpful! Clearly, when unscrewed the 76 (along with the FS60) would be difficult to beat for portability but I’m still surprised how compact the FC100 is there. 

[Stu]

22 minutes ago, Icesheet said:

but I’m still surprised how compact the FC100 is there.

Yep, that’s why they are so popular I think; great optically and about the most compact and lightest, readily available 4” around.

[Littleguy80]

10 minutes ago, Stu said:

Yep, that’s why they are so popular I think; great optically and about the most compact and lightest, readily available 4” around.

That was actually the biggest deciding factor for me on buying the FC100. I wanted to upgrade my 80mm frac with a 100mm that I could still take as hand luggage. The FC100 was the only one that I found. It’s awesome to be able to bring a scope or that quality on holiday with me. 

[Cometeer]

Twins! I highly recommend the K-Astec TB-80AS rings if you are looking for new ones. I mount a Vixen dovetail on one side, an arca swiss dovetail on another, and a finder clamp on the 3rd side. These are lighter than More Blue rings too.

[Stu]

1 hour ago, Cometeer said:

Twins! I highly recommend the K-Astec TB-80AS rings if you are looking for new ones. I mount a Vixen dovetail on one side, an arca swiss dovetail on another, and a finder clamp on the 3rd side. These are lighter than More Blue rings too.

They look nice, sourced directly from Japan?

[Cometeer]

50 minutes ago, Stu said:

They look nice, sourced directly from Japan?

Yep. Also, the part numbers for the K-Astec plates are DP45-190 (vixen) and DP38-190 (arca).