I wanted to perform 2D classification on an image dataset. For that I was trying to import a particle stack from micrographs. import particle stack requires metadata as an input field, I dont have any metdata how should I proceed?
Where did you get the 2D stack from? Did you simulate it? If so, you will need to create a metadata file yourself, using the parameters you used for the simulation. If you are importing from RELION, you can use the particles.star file which is part of the extract/stack job. From cisTEM, you will need to export to RELION star first. Uncertain how to proceed with EMAN2, not used it for years.
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Thanks for your reply, I am not sure about this RELION. I just have the image dataset in .mrc format and wanted to perform 2D classification.
Without knowing more about the provenance of the data, it’s difficult to impossible to guess our way to a potential solution for your question. 
If you know the acceleration voltage and spherical aberration of the microscope or simulation parameters, you can brute force it by plugging in some numbers and repeatedly refining defocus and astigmatism for the particles (checking that refined parameters “make sense” after each step) but knowing (a) where you got the data from, (b) whether you know whether it is real or simulated, (c) whether you know what parameters the hardware or simulation used… it’ll be a case of plug in numbers over multiple tries and see what works best - but that is obviously, painfully fraught with pitfalls.
You might try a couple of the tutorials in the guide to understand the workflow. Have you picked particles from the micrographs (manual or blob or template picking)? Did you run extraction job? Then you drag the extraction particles output to the 2D job.
If instead you have a .star file that has all the particles identities listed inside, you tell the file system where that metadata file is located so it can surmise where each extracted particle is located
Thanks for your reply, I have imported the micrographs. While I try to perform patch CTF estimation I receive message like image is missing or incomplete. could you please guide me to this 2D classification … I am new to cryosparc.
micrographs contain many particles (usually). particle picking assigns coordinate positions of where the particles are located. then we run extraction job to cut out small individual pictures of each particle (so thousands->millions in a stack). then you can run 2D classification to sort and combine these individual pictures into groups that look the same. it also refines the particle picked locations a bit.
definitely the guide.cryosparc.com should be your friend, and there are some beginning-to-end tutorials to understand the whole process and how to achieve it in cryosparc gui
Thanks for your reply. I followed your guide and tried creating template picker but received the error "float division by zero ". Also I tried blob picker with micrographs as an input to the blob picker job but the blob picker completed the job with 0 particles being outputted. I am not sure how to take this forward.