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by to11mtm 74 days ago
...

My only curiosity, and yeah I know orders of significance etc...

Buuuuut I wonder why they didn't consider a Z5[0][1] and the Z mount 14-24, or the Z5 with an adapter for the F mount 14-24....

There's at least a pound of weight savings on the table.

Specifically, I wonder if it's a fun reason? i.e. it would be interesting if there was a technical reason like 'IBIS fails miserbly' or 'increased sensor resolution adds too much noise' (even at that ISO you gave from the EXIF...)

[0] I'm really more of a Sony person but am thus keenly aware about importance of UX feel, so I tried to keep the question apples to apples here.

Edited to add:

[1] Per [0] I may be stupid in thinking the Z5 is a 'at least minimal' substitute so happy to learn something here.

2 comments

They have a Z9 on board for radiation testing, but the D5 is the primary body for imaging on this mission IIRC
The D5 has been used on the ISS since 2017, including EVAs:

* https://en.wikipedia.org/wiki/List_of_cameras_on_the_Interna...

The ISS now (also?) has Z9s. So they're both generally known-quantities.

Yeah other folks gave better insight while I was writing my comment, oops...
When you're riding a rocket that weighs 3.5 million pounds...
Is that the Rocket or the Craft+Mission payload?

My understanding is it's on the order of 5-10 pounds of rocket juice to get one pound of something to LEO, thus the question.

At 3.5 mil pounds that has to be the full rocket. But quick [1]googling is giving an even higher total mass number...

1. https://www.nasa.gov/wp-content/uploads/2026/01/sls-5640-sls...

Mass higher up the rocket costs several multiples more mass in propellant and propellant handling lower in the rocket. And the more deltaV you want the higher the multiplication. (If I remember right some weight issues of some kind on the Apollo capsule and or lander required a common bulk head in the first stage to make up the performance loss!)

However cameras probably fall into the variance in astoraunt weight somewhat.